• Earthquakes and Structures
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• v.10 no.1
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• pp.53-71
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• 2016

Unconventional computer vision and image processing techniques offer significant advantages for experimental applications to shaking table testing, as they allow the overcoming of most typical problems of traditional sensors, such as encumbrance, limitations in the number of devices, range restrictions and risk of damage of the instruments in case of specimen failure. In this study, a 3D motion optical system was applied to analyze shake table tests carried out, up to failure, on a natural-scale masonry structure retrofitted with steel reinforced grout (SRG). The system makes use of wireless passive spherical retro-reflecting markers positioned on several points of the specimen, whose spatial displacements are recorded by near-infrared digital cameras. Analyses in the time domain allowed the monitoring of the deformations of the wall and of crack development through a displacement data processing (DDP) procedure implemented ad hoc. Fundamental frequencies and modal shapes were calculated in the frequency domain through an integrated methodology of experimental/operational modal analysis (EMA/OMA) techniques with 3D finite element analysis (FEA). Meaningful information on the structural response (e.g., displacements, damage development, and dynamic properties) were obtained, profitably integrating the results from conventional measurements. Furthermore, the comparison between 3D motion system and traditional instruments (i.e., displacement transducers and accelerometers) permitted a mutual validation of both experimental data and measurement methods.

• International Journal of Advanced Culture Technology
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• v.9 no.3
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• pp.188-201
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• 2021

The purpose of this study is to analyze the effects of online home learning in connection with extracurricular activities for lifelong education for the disabled in university on the cooking aids skills of cafeterias for the job search persons with developmental disabilities. Three people with job search developmental disabilities who have been in a state of unemployment for three years after graduating from a special high school course participated in the experiment. In order to verify the meaningful functional relationship between independent variables and dependent variables, multiple probe design across subjects, one of the main techniques of a single object study, was used. The experimental conditions according to the research design consisted of the steps of baseline, intervention, maintenance, and generalization. The dependent variable of this study is the restaurant cooking aid skills in the cafeteria, and three subskills such as side dish arrangement, sink arrangement, and dish washing were combined by task analysis. And the independent variable of this study was composed of procedures and methods to teach the environment, tools and materials related to the performance of dependent variables to the developmental disabled people at home by using real-time image technique through zoom service, and the contents of the performance by stages of task analysis. In addition, independent variables were applied to the subjects in the course of the extracurricular activities with the theme and contents of lifelong education for the disabled at university. Students who completed the above extracurricular activities practiced the intervention scene of the researcher through the screen sharing of zoom service. As a result, the subjects with developmental disabilities effectively acquired and maintained the positive response performance of dependent variables through independent variables. The subjects also showed high positive responses to generalization tests conducted in kitchens in cafeterias located elsewhere in the same university.

• The Journal of the Convergence on Culture Technology
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• v.5 no.1
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• pp.243-248
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• 2019

As digital media technology continues to evolve, media arts are being created using new technologies. Among them, interactive media provides new experience and interest to the audience in that the audience is completed only by participating in the works. The use of these characteristics as a marketing strategy has led to an increase in sales and a positive image of the company. Through this study, we analyze the case of interactive media contents and infer the usage plan and elements. In addition, we propose a prototype of interactive media contents that can be used as a strategic marketing element by exploring ways to utilize interactive media as a marketing element of the film industry. This suggests the development direction of interactive media that provides a continuous and new sense of immersion to the audience, and suggests subsequent research on effective use of the industry as well as movie marketing.

• The Journal of Advanced Prosthodontics
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• v.14 no.3
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• pp.162-172
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• 2022

PURPOSE. The present study aims to analyze the effect of abutment neck taper and types of cement on the amount of undetected remnant cement of cement-retained implant prostheses. MATERIALS AND METHODS. Three neck taper angles (53°, 65°, 77°) and three types of cement (RMGI: resin-modified glass ionomer, ZPC: zinc phosphate cement, ZOE: zinc oxide eugenol cement) were used. For each group, the surface percentage was measured using digital image and graphic editing software. The weight of before and after removing remnant cement from the abutment-crown assembly was measured using an electronic scale. Two-way ANOVA and Duncan & Scheffe's test were used to compare the calculated surface percentage and weight of remnant cement (α = .05). RESULTS. There were significant differences in remnant cement surface percentage and weight according to neck taper angles (P < .05). However, there were no significant differences in remnant cement surface percentage and weight on types of cement. No interaction was found between neck taper angles and types of luting cement (P > .05). The wide abutment with a small neck taper angle showed the most significant amount of remnant cement. And the types of luting cement did not influence the amount of residual cement. CONCLUSION. To remove excess cement better, the emergence profile of the crown should be straight to the neck taper of the abutment in cement-retained implant restoration.

• Journal of the Korean Geotechnical Society
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• v.23 no.9
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• pp.29-37
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• 2007

The experiments have been conducted on Kaolinite in laboratory to investigate the development of shrinkage cracking and propose a simple model. Image analysis method consisting of control point selection(CPS) technique is used to process and analyze images of soil cracking captured by a digital camera. The distributions of crack length increment and crack area increment vary as a three-step process. These steps are regarded as stages of soil cracking. They are in turn primary crack, secondary crack and shrinkage crack stages. In case of crack area, the primary and secondary stages end at normalized gravimetric water content(NGWC) of 0.92 and 0.70 for different specimen thicknesses respectively. In addition, the primary stage in case of crack length also ends at NGWC of 0.92 while the secondary stage stops at NGWC of 0.79, 0.82, and 0.85 for the sample thicknesses of 0.5, 1.0, and 2.0 cm respectively Based on the experimental results, the distributions of crack length increment and crack area increment appear to be linear with a decrease of NGWC. Therefore, the development of shrinkage cracking is proposed typically by a simple model functioned by a combination of three linear expressions.

• The Journal of Engineering Geology
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• v.9 no.2
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• pp.161-176
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• 1999

The objectives of this study are to analyze the changes of geo-surface topography in the Siwha embankment and the Ahsan city area by the image processing of Landsat Thematic Mapper data, and to estimate the reclaimed amount of the exposed tidal flat in the Siwha area using the GIS. False color composite, Tasseled cap, NVDI(normalized difference vegetation index), and supervised classification techniques were used to analyze the distribution of sediments and the aspect of topographical variations caused by artificial human actions. The total amount of the exposed tidal flat was estimated on the basis of the database snch as aerial photography, hydrographic chart, geological map, and scheme drawing in the Siwha area. The possible excavation regions for a seawall were predicted analyzing the supervised classification image of Landsat TM data. Tasseled cap images were used to observe the distribution of sediments. The difference of the NDVI images between spring and summer seasons indicates that deciduous and coniferous forests were distributed over the whole areas. The total fill-volume of the exposed Siwha tidal flat and the fill-volume of the construction planning seawall were calculated as $581,485,354\textrm{m}^3{\;}and{\;}3,387,360\textrm{m}^3$, respectively, from the digital terrain analysis. Daebu Island, Sunkam Island, and the part of Songsan-myeon were chosen as the cut area to make the seawall, and their cut-volumes were estimated as $5,229,576\textrm{m}^3,{\;}79,227,072\textrm{m}^3,{\;}and{\;}47,026,008\textrm{m}^3$, respectively. Therefore, the cut-volume of Daebu Island alone among three areas was sufficient to make the seawall.

• Trans-
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• v.12
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• pp.51-79
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• 2022

This study investigates the methods for deriving colors which can serve as a reference to users such as designers and or contents creators who search for online images from the web portal sites using specific words for color planning and more. Two experiments were conducted in order to accomplish this. Digital scenery photos within the geographic scope of Korea were downloaded from web portal sites, and those photos were studied to find out what colors were used to describe daytime and nighttime. Machine learning was used as the study methodology to classify colors in daytime and nighttime, and KSCA was used to derive the color frequency of daytime and nighttime photos and to compare and analyze the two results. The results of classifying the colors of daytime and nighttime photos using machine learning show that, when classifying the colors by 51~100%, the area of daytime colors was approximately 2.45 times greater than that of nighttime colors. The colors of the daytime class were distributed by brightness with white as its center, while that of the nighttime class was distributed with black as its center. Colors that accounted for over 70% of the daytime class were 647, those over 70% of the nighttime class were 252, and the rest (31-69%) were 101. The number of colors in the middle area was low, while other colors were classified relatively clearly into day and night. The resulting color distributions in the daytime and nighttime classes were able to provide the borderline color values of the two classes that are classified by brightness. As a result of analyzing the frequency of digital photos using KSCA, colors around yellow were expressed in generally bright daytime photos, while colors around blue value were expressed in dark night photos. For frequency of daytime photos, colors on the upper 40% had low chroma, almost being achromatic. Also, colors that are close to white and black showed the highest frequency, indicating a large difference in brightness. Meanwhile, for colors with frequency from top 5 to 10, yellow green was expressed darkly, and navy blue was expressed brightly, partially composing a complex harmony. When examining the color band, various colors, brightness, and chroma including light blue, achromatic colors, and warm colors were shown, failing to compose a generally harmonious arrangement of colors. For the frequency of nighttime photos, colors in approximately the upper 50% are dark colors with a brightness value of 2 (Munsell signal). In comparison, the brightness of middle frequency (50-80%) is relatively higher (brightness values of 3-4), and the brightness difference of various colors was large in the lower 20%. Colors that are not cool colors could be found intermittently in the lower 8% of frequency. When examining the color band, there was a general harmonious arrangement of colors centered on navy blue. As the results of conducting the experiment using two methods in this study, machine learning could classify colors into two or more classes, and could evaluate how close an image was with certain colors to a certain class. This method cannot be used if an image cannot be classified into a certain class. The result of such color distribution would serve as a reference when determining how close a certain color is to one of the two classes when the color is used as a dominant color in the base or background color of a certain design. Also, when dividing the analyzed images into several classes, even colors that have not been used in the analyzed image can be determined to find out how close they are to a certain class according to the color distribution properties of each class. Nevertheless, the results cannot be used to find out whether a specific color was used in the class and by how much it was used. To investigate such an issue, frequency analysis was conducted using KSCA. The color frequency could be measured within the range of images used in the experiment. The resulting values of color distribution and frequency from this study would serve as references for color planning of digital design regarding natural scenery in the geographic scope of Korea. Also, the two experiments are meaningful attempts for searching the methods for deriving colors that can be a useful reference among numerous images for content creator users of the relevant field.

• Korean Journal of Digital Imaging in Medicine
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• v.12 no.1
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• pp.33-41
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• 2010

National Cancer Screening Project and Korean Society of Breast Imaging recommend that breast cancer screening should be performed on those aged 40 and above. Nevertheless, this recommendation is usually ignored by a number of medical institutions. The purpose of this study is to emphasize the necessity of an age limitation in screening mammography. Ten institutions were randomly selected and telephone inquiries about patients' age limitation and internal guidelines were set up. The 3,214 women, who underwent screening mammography through 'GE Senography 2000D' in each hospital, were classified into five groups according to age(from 20s to 40s, at intervals of 5). And then, collected data was analyzed by a radiologist in accordance with ACR-BIRADS(American College of Radiology Breast Imaging Reporting and Data System), through which breast parenchymal density and the results of analysis were categorized in order to predict the sensitivity of mammography. Information about craniocaudal-view mammograms was automatically produced by use of GE Senography 2000D, and the average glandular dose was retrospectively analyzed through the program 'Excel 2007.' Two institutions did not set the age limitation. Other seven institutions internally allowed those who wanted to receive mammography regardless of age. Approximately 99% of those aged 20 to 29 were judged as having the dense breast. In those aged 35 to 39, breast parenchymal density tended to be lower, but the fatty breast to increase. In the case of 'category-zero' that does not need additional tests, the rate of 'heterogeneously dense' and 'extremely dense' reached to 83.1% and 15.1% respectively. Regarding dense breasts, there was no sufficient information for image reading. The glandular dose, applied to 3,214, was 1.47mGy on the average. In those aged 20 to 24 who are sensitive to radiation, the average glandular dose indicated 1.59mGy. Those aged 35 and above showed the lowest value, 1.43mGy. In those aged 35 to 39, the breast tended to change from denseness to fattiness. The average glandular dose was lowest in those aged 35 and above, which suggests that screening mammography should be periodically performed on those aged 35 and above in order that breast cancer may be early detected. On the other hand, in those aged less than 35, it is difficult to analyze mammograms due to the high density of breast parenchyma, and also retakes become frequent. In particular, subjects may be exposed to excessive doses. Accordingly, it should be substituted by breast self-examination or clinical breast examination. In case of need, it is advisable to perform ultrasonography.

• Journal of Digital Convergence
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• v.18 no.11
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• pp.571-579
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• 2020

The purpose of the study was to explore modern people's emotion regarding sex commercialization related to the abolition of grid girl. To collect data, based on 'reply journalism', this study collected 15 blogs, 10 online cafe contents, 1 youtube video clip, and 364 replies associated with the three online contents. To analyze the data, interpretive text analysis was utilized and the following results were obtained. As results, the analysis on the replies shows that the most strong emotion of the modern people regarding the abolition of grid girl is anti-feminism that includes hatred toward feminists and even females, criticism on feminism, and notion of 'women's enemy is women themselves'. In addition, sympathy toward racing models who lost their jobs, requirement of same abolition to the people with similar occupations, spatial separation between men and women, and consent on the abolition of racing models were found. Unlike the feminists' emotion regarding sex commercialization and racing models, modern people's emotion was different from them. Rather, ordinary people have doubted and even criticized on the rationales of feminism. Unlike feminists' notion about sex commercialization of racing models, these results imply that social image of racing models has changed and wish their position is respected as an ordinary occupation, without issues of sex commercialization.

• Journal of Digital Contents Society
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• v.16 no.2
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• pp.227-234
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• 2015

Recently, there is more and more demand on broadcasting display environment that provides a sense of realism basically with high quality and high definition as in UHDTV, so various kinds of 4K cameras have been released. Super 35mm sensor 4K/UHD cameras being generally used can be usefully applied to the single camera-based system such as advertisements, dramas, nature documentaries, and culture programs. However, in the multicamera-based system such as entertaining programs, sports, and concerts, relay broadcasting may face limitations as there are restrictions of close-up or tight shots according to the distance. Besides, 4K lenses are not enough compared with the previous HD lenses' group, so there are limitations in camera photographing shots that have been realized in HD filming. Therefore, to complement this, the use of 2/3 inch sensor 4K/UHD cameras is being demanded, and it is also needed to use various lenses' groups to produce UHD image contents. Accordingly, this study used Grass Valley's LDX 4K/UHD camera to analyze its applicability based on the picture quality test at the use of HD lenses in 2/3 sensors and also the possibility of its efficient application.