• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.549-552
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• 2008

Corrosion of reinforcing steel is prohibited under normal condition by the alkalinity of the pore water in the concrete. But the probability of steel corrosion becomes higher when the chloride ions are introduced into the concrete. Steel corrosion is decisive factor for the determination of service life of the marine concrete structures because chloride ions are abundant in the sea. In this paper, chloride penetration analysis for the rectangular pier in the marine environment is performed considering the diffusion movement of chlorides. Result reveals that the chloride concentration in the corner bar is higher than that of in the side bar with rectangular pier. Also the time to the specified accumulation of chloride in the corner bar is much shorter than that in the side bar. Because the corrosion initiation time of corner bar is half as much as that of side bar, service life for the rectangular pier in marine environment should be determined with respect to the coner bar.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.34 no.4
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• pp.51-58
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• 2018

Various types of pilotis frames are used on the ground level of high-rise buildings. In some cases, their interior finishing is destroyed by strong winds or typhoons. In the case of a corner pilotis, the peak wind pressure coefficients were greater on the ceiling than they were on the wall for all wind angles. Specifically, on the ceiling portion of a pilotis, the coefficient increased gradually from the outside to the inside in a symmetrical form that centered on the corner edge. However, the minimum peak wind pressure coefficient was greater at the center of the ceiling than it was on the edge of the pilotis' interior. Additionally, the higher the height of the pilotis, the greater the peak wind pressure coefficient was due to the turbulent flow that occurs within a pilotis. In this study, we evaluated peak wind pressures to design an interior finishing for the end edge of a pilotis and for corner piloti. In terms of specific wind angles, the maximum and minimum peak wind pressure coefficients were each observed. They were a maximum of $320^{\circ}$ and a minimum of $270^{\circ}$ for corner piloti and $0^{\circ}$ and $270^{\circ}$, respectively, for the end edge piloti.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.24 no.8B
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• pp.1518-1531
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• 1999

The reconstructed images from highly compressed MPEG or H.263 data have noticeable image degradations, such as blocking artifacts near the block boundaries, corner outliers at cross points of blocks, and ringing noise near image edges, because the MPEG or H.263 quantizes the transformed coefficients of 8$\times$8 pixel blocks. A post-processing algorithm has been proposed by authors to reduce quantization effects, such as blocking artifacts, corner outliers, and ringing noise, in MPEG-decompressed images. Our signal-adaptive post-processing algorithm reduces the quantization effects adaptively by using both spatial frequency and temporal information extracted from the compressed data. The blocking artifacts are reduced by one-dimensional (1-D) horizontal and vertical low pass filtering (LPF), and the ringing noise is reduced by two-dimensional (2-D) signal-adaptive filtering (SAF). A comparison study of the subjective quality evaluation using modified single stimulus method (MSSM), the objective quality evaluation (PSNR) and the computation complexity analysis between the signal-adaptive post-processing algorithm and the MPEG-4 VM (Verification Model) post-processing algorithm is performed by computer simulation with several MPEG-4 image sequences. According to the comparison study, the subjective image qualities of both algorithms are similar, whereas the PSNR and the comparison complexity analysis of the signal-adaptive post-processing algorithm shows better performance than the VM post-processing algorithm.

• Journal of architectural history
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• v.16 no.2
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• pp.137-152
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• 2007

The purpose of this article is making investigation of the principal composition of the twin-pagodas in Buddhist temple through ornaments of a case preserving relics of Buddha in the east and west pagodas of Gameunsa temple. This research has an important meaning in clarifying that the concept of placement two Buddhas together with lotus sutra, which was only applied to Bulkuksa temple, has been extended to Gameunsa temple. And this observation gave us a clear explanation for the principal composition at the twin-pagodas in Buddhist temple plans. The author obtained the following conclusion from this article : The cases preserving relics of the Buddha for the west and east pagodas are globally in similar form as the type of a royal palace. But the different points between eastern and western can be seen on the existence of Buddhist statues on the base floor, set-up of the gate at railings, and 4 lion statues at a coner of the base floor. In the western pagoda, there are Buddha statues above the base-floor of the cases preserving relics. These Buddha statues are composed of a boy monks and angels with playing music for the praise of the Sakyamuni Buddha lecturing the Lotus sutra at YoungChui Mountain. On the other hand, in the eastern pagoda, Buddha statues on the cases preserving relics are composed of a the Four Devas and monks as a defending God of the nation of Buddha. In the eastern pagoda, one can see something that does not exist in the western pagoda, which is a gate located in railing of a case preserving the relics. This gate described the scene of the Sakyamuni Buddha entering into the pagoda of 7 treasures. In a corner of the case preserving relics in the eastern pagoda, there is another thing which does not exist in the western pagoda. This is a sculpture of a lion which symbols the seat of Lion supporting the Buddha in the Dabotap(the pagoda of 7 treasures). When we observe the form and structure, the descriptions at the railings, the gate, the shrine, the statue of a lion, and the accessories in jewelries, at the cases preserving the relics in the eastern pagoda, one can realize that they have the same combination structures between the ones at Dabotaps in Bulguksa temple and those in China as well as in Japan, all of which represent the Gyun-Bo-Tap-Pum of Lotus Sutra. Among the distribution rules in the twin-pagodas in Buddhist temple, the application of the ideal of lotus was known to be effected only to Bulguksa temple. But from the result of the present article, it is more clearly proved by applying the Gameunsa temple that the distribution theory in the twin-pagodas in Buddhist temple was in fact based on the ideal of lotus.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.21 no.7
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• pp.769-777
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• 2010

In this paper, a switchable circularly polarized microstrip patch antenna using PIN diodes and corner slots on ground plane is proposed at 2.4 GHz. The proposed antenna has a square microstrip patch and ground plane that consists of two pair of slots and PIN diodes. The electrical lengths of the slots are adjusted by using the switching characteristic of the PIN diode, so the polarization of the proposed antenna can be switchable between linear, left-handed(LH) and right-handed(RH). By separating the ground plane for the DC bias, the size reduction effect is also obtained. When the proposed antenna is operated as linear polarization, the return loss and impedance bandwidth are 15 dB, 59 MHz, and when operated as LH and RH polarization, the minimum axial ratio and 3-dB axial ratio bandwidth are 1.17 dB, 1.67 dB, 28 MHz, and 32 MHz, respectively.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.4
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• pp.358-365
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• 2017

In this paper, we propose an object recognition method using image information to improve the efficiency of visual servoingfor industrial manipulators in industry. This is an image-processing method for real-time responses to an abnormal situation or to external environment change in a work object by utilizing camera-image information of an industrial manipulator. The object recognition method proposed in this paper uses the Otsu method, a thresholding technique based on separation of the V channel containing color information and the S channel, in which it is easy to separate the background from the HSV channel in order to improve the recognition rate of the existing Harris Corner algorithm. Through this study, when the work object is not placed in the correct position due to external factors or from being twisted,the position is calculated and provided to the industrial manipulator.

• Journal of the Korean Institute of Landscape Architecture
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• v.36 no.3
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• pp.75-84
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• 2008

The purpose of this research is to find the visual characteristics and geographic structure in a landscape of mountains in Yangsan City. In order to carry out this study, 40 view points of 6 mountains in Yangsan City were selected to experience the mountainscape. The results are as follows. The mountainscape of Yangsan City was confirmed from the view point to the object of view as ranging in middle distance reverse, the angle of elevation 11${\sim}13^{\circ}$ which give the impression of confronted to the mountain, and the horizontal angle 50${\sim}90^{\circ}$ which gives the impression of vastness. This shows that mountainscapes are perceived impressively when seeing the mountain with the meaning to feel the texture of the mountain as a confrontational relationship rather than a pictorial relationship. The geographic structure of the view point which occurs in scenes of impressive experience is classified into eight types and its characteristics are investigated. The first type is corridor, and it emerges in a long narrow linear structure made from the surrounding environment with buildings or street trees. The second is tunnel in which a vision and light hidden while passing underneath a bridge, high-level road, or inside a tunnel can be seen. Third, the maze is formed by the mountain shape. The hill spur emerges when the direction of traffic changes after turning the coner of a building or mountain edge. The hill ground emerges at the top of a hill slope. Next, parallel emerges when the observer and the mountain are in the same direction of process. Confrontation occurs when confronting an isolated mountain. Finally, the view point emerges when passing through major points such as a bridge or square and the boundary of a village or city. This research arranged visual conditions that create impressive mountainscapes. Geographic characteristics in terms of Types that make possible to experience mountainscapes were described. The results of this research will be basic data collected for the management and preservation of mountainscapes and for landscape effect evaluation. Furthermore, this research suggests theoretical evidence to preserve and manage geographic structures that create view experiences as well as to preserve the landscape in terms of view points.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.34 no.1
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• pp.18-39
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• 2016

The study pertains to reviewing and discussing of the master plan of the main buildings in the palaces of Joseon Dynasty regarding on a Feng Shui concept that has been implemented on the palace axis that is originated from the main mountain. Gyeongbokgung (景福宮) Palace is located on the northwest coner of Hanyang (漢陽) and on the tip of the main mountain which is in contrast a quite distinguishable from the location of the Fobidden city in Beijing located in the middle of a vast basin. Changdeokgung (昌德宮) Palace as well is also located on the tip of Eungbong (鷹峯), a part of Samkaksan (三角山) mountain, of which the locations were designed for the palaces to receive the benevolent force from the main mountain. The same concept was also applied to appointing the ideal location of the maJor buildings such as Jungjeon (正殿: The throne hall), Pyunjeon (便殿: The king's office) and Chimjeon (寢殿: The king and queen's residence) in the palace that must receive the benevolent force from the qui stream also originated from the main mountain, as such that the buildings have in close relationship with the king. Amisa (蛾眉砂) had been considered as an important geographical milestone of the estate where the palace is located, especially as the guiding landmark for other buildings that must be on the land axis. The land axis with the Amisa as the starting point attributed the Feng Shui as an important measure that determines the location and the shape of other buildings. The buildings location was appeared as having the conceptual buildings location as 'front office-back bedroom building (前朝後寢)' and 'three gates-three sectors (三問三朝)' as per the Rites of Zhou (周禮). On both palaces, Amisa is located on the benevolent point of the land, and the king's bed room buildings are located near the Amisa. The main offices were located on the south of the king's bed room buildings. By practicing this type of concept, consequently the king can receive the pure benevolent force first. In the case of the clearly distinguished locations of the buildings in Gyeongbokgung Palace, Chimjeon, Pyunjeon and Jungjeon were located on the same main qui stream. However, in Changdeokgung Palace where scattered qui stream is observed, the buildings are located on the scattered qui stream. The study found that the type of location of Jungjeon receives least amount of benefit from the Feng Shui but reflects primarily the king's authority rather than order and formality of the space.