• Journal of the Korean Geotechnical Society
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• v.22 no.10
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• pp.101-110
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• 2006

In general, environment-induced vibration propagates from the center of source to the destination through ground. In fact, the mechanism of wave propagation is highly dependent on the ground conditions, and various methods to protect structures from such a ground vibration have been proposed. The method of wall barrier has been frequently used to cut off ground vibration effectively. However, the capability of wall barrier may be affected by various factors like constituent material of it. Therefore, it is important to figure out appropriate material for the wall barrier. This study is focused on the effect of EPS on the vibration protection. Centrifuge model tests were performed. Two types of models such as a cylindrical and a rectangular wall were used. For the cylindrical type of wall, installation depth was changed, while the length of the wall varied fur the rectangular type to figure out the capability of vibration protection.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.3
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• pp.1264-1286
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• 2018

In this paper, a novel background prior-based salient object detection framework is proposed to deal with images those are more complicated. We take the superpixels located in four borders into consideration and exploit a mechanism based on image boundary information to remove the foreground noises, which are used to form the background prior. Afterward, an initial foreground prior is obtained by selecting superpixels that are the most dissimilar to the background prior. To determine the regions of foreground and background based on the prior of them, a threshold is needed in this process. According to a fixed threshold, the remaining superpixels are iteratively assigned based on their proximity to the foreground or background prior. As the threshold changes, different foreground priors generate multiple different partitions that are assigned a likelihood of being foreground. Last, all segments are combined into a saliency map based on the idea of similarity voting. Experiments on five benchmark databases demonstrate the proposed method performs well when it compares with the state-of-the-art methods in terms of accuracy and robustness.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.872-879
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• 2010

High rock-fill embankment is relatively flexible, which makes crest of embankment subject to excessive amplification in displacement due to earthquake loading. To overcome problems related with site response in high embankment, it is essential to evaluate shear-wave velocity profile of the embankment with improved accuracy and reliability. In this aspect, an experimental research was performed to answer how to perform surface-wave tests and to analyze measurements at an embankment site with a sloping ground surface. Unlike flat ground surface, sloping ground may hamper and slow down propagation of surface waves due to multiple reflections and refractions in embankment. To figure out this reasoning for the effect of multiple reflections and refractions due to sloping surface, surface wave tests were performed at a reservoir embankment of Chung-Song in North KyeongSang Province. Parameters involved in surface wave tests at non-flat surface, including source directionality, geometry-related constraint and frequency components in source function, were investigated using field measurements.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.7 no.3
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• pp.160-166
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• 1978

Heat loss to the ground in ondol heating system is analyzed mathematically using conformal mapping and variable transformations, Both two-and three-dimensional systems are analyzed. Heated house is assumed to be rectangular shape. Mean value of heat loss to the ground can be obtained using Figure 2. Effects of thermal parameters to heat loss are discussed. Numerical examples are also given.

• PNF and Movement
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• v.19 no.2
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• pp.287-301
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• 2021

Purpose: Gait training for stroke patients focuses on adjusting to new environments to facilitate outdoor walking. Therefore, the purpose of this study was to identify the effects of various ground obstacle walking combined with treadmill walking on the gait parameters and functional gait ability of chronic stroke patients. Methods: Twenty-four chronic stroke patients were divided into two groups: an experimental group (n = 12) and a control group (n = 12). The experimental group received a combined gait training using various ground obstacle walking and treadmill walking (VGOW) five times/week for four weeks. The control group received traditional treadmill training (TW) five times/week for four weeks. Patients were evaluated using the figure-8 walk test (F8WT) and the Functional Gait Assessment (FGA) before and after each intervention. Results: The ANCOVA results showed that both treatments significantly influenced F8WT steps, F8WT time, and FGA score. The paired t-test results showed a significant improvement in F8WT steps, F8WT time, and FGA score in the experimental group compared to those in the control group. Conclusion: Combined gait training using various ground obstacle walking and treadmill walking can improve gait ability in chronic stroke patients.

• Journal of Industrial Technology
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• v.29 no.B
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• pp.73-80
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• 2009

This paper is to investigate effect of B.G.I (Best Grouting Innovation) method on reinforcing ground. In this thesis, extensive literature review was performed to summarize theoretical backgrounds of grouting and to compare the applicability of different grouting methods. Unconfined compression test with specimen prepared by injecting different grouts of B.G.I, S.G.R and L.W methods and by changing the curing time were carried out to figure out characteristics of initial unconfined compression strength mobilized in the early stage. As results of test, the compression strength increases with curing times and specimen prepared with grouts of B.G.I method show greater values than others. On the other hands, the measured values of pH are in the range of 7-10 during tests. In field, preliminary construction to main construction at several sites were performed to confirm the effect of reinforcing the ground by application of B.G.I method. From the results of permeability test in field, SPT test and phenol reaction test, it was found that N values after grouting are greater than those before grouting and values of permeability in grouted ground is reduced significantly.

• Journal of the Korean Society of Costume
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• v.56 no.9 s.109
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• pp.37-49
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• 2006

The purpose of this study is to figure out the types and characteristics of the twill damask fabrics through literatures review of both domestic and Chinese documents and records. In addition, the study aims to review the characteristics of the twill damask fabrics found at Sukga Pagoda. The twill damask fabrics can be categorized in terms of the weaving method into Float Pattern on a Tabby Ground, Twill Pattern on a Tabby Ground, Float Pattern on a Twill Ground, Twill Pattern on a Twill Ground, and Without Pattern on a Twill Ground. The fabrics ran also be divided in terms of their name into Ki, Neung, and Munju. Four items of twill damask fabrics were found inside the Sukga Pagoda. All of them are Twill Pattern on a Twill Ground. At the primitive level of weaving skill, twill damask fabric was made by adding patterns with twill damask or BuJik on the background of plain weave. At more advanced level, the fabrics are weaved by making patterns with twill damask or BuJik on the background of twill damask. Compared to the relics of Koryo and Chosun Dynasty, these twill damask fabrics were loosely weaved with relatively thick thread.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.49 no.5
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• pp.399-405
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• 2021

In the present study, ground tests and CFD simulations for a ducted fan system were performed to verify the hovering performance of the ducted fan system designed by KARI rotorcraft team. Six blades were composed for the ducted fan, and target rotating speed of the fan was decided to 4,000 RPM. Collective pitch angles were considered from 20 degrees to 36 degrees. The test data were obtained by increasing the rotating speed up to 4,000 RPM in 1,000 RPM increments. The CFD simulations were considered only 4,000 RPM of rotating speed. The hovering performance was represented by thrust, power, duct thrust ratio, and FM(Figure of Merit). Reliability of the performance results was ensured through the test and simulation results, and it was found that the target performance was achieved under conditions above 31 degrees of the pitch angle.

• Journal of the Korean Society of Clothing and Textiles
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• v.16 no.1 s.41
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• pp.111-122
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• 1992

Studying the dress style of the Buddhist Goddess of Mercy SU WOL KWAN EUM DO (Drawings on the Buddhist Goddess of Mercy who is watching the Moon reflected in the still water), it is composed of a splendid, jewel crown with five colors, a light and flimsy, non-colored veil with many kinds of gold·plated patterns. This gold·plated carapace figures on a scarlet ground are drawn on the veil and the oval-type flower figures mixed with a scarlet lotus blossom ard arranged. An arabesque pattern of BOSANGHWA (an imaginary, Buddhistic flower figure) is mainly used for both line decorations and necklace. Like this, various kinds and types of figures are in harmony in spite of many changes in figure design. The SU WOL KWAN EUM DO in Koryo dynasty is full of colorful, subtle, harmonious figures which are unique style, which cannot be found in japan, China, and so on. In other words, most of most of dress patterns which are shown in SU WOL KWAN EUM DO are China ink paintings with mountains and waters as its setting. In case of color painting, figure designs are seldom used. The dress pattern in SU WOL KWAN EUM DO of koryo dynasty is characteristic of its variety and magnificent colors.

• Journal for History of Mathematics
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• v.19 no.3
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• pp.43-56
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• 2006

This paper aims to introduce a construction method for the 'Wooden Die for Drinking Game' and to find some geometrical structures and mathematics educational viewpoints. As the results, we get two methods which are eventually same with Figure 5 and Figure 6-3. We proved the ground that classical probability of this Die's each side showing up is one out of fourteen and introduced few other empirical probabilities with Table 1 to Table 3. Also, some Chinese characters were corrected and re-interpreted. In fact, 象人打鼻 changed to 衆人打鼻, and 醜物 is interpreted as 'ugly animal' such as frog, toad, earthworm or pine caterpillar.