• Journal of the Institute of Electronics Engineers of Korea SD
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• v.45 no.12
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• pp.15-21
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• 2008

Several shared buses are divided hierarchically and connected with a bridge in the bus topology that consists of many components such as SoCs. Because the bridge topology is capable of the simultaneous communication of components in the several buses, the bus performance has improved definitely. However, when the inter-bus data transaction happens, the latency increases seriously in the bridge block. In this paper, a variety of bridge architectures are analyzed in the point of view of merit and demerit. Superior frying bridge topology is proposed in the aspects of performance, IP reusability, timing margin, gate count and circuit complexity. In contrast with the conventional bridge that has only a role to switch the inter-bus data, the frying bridge can communicate directly between the bus and the slave, which decreases the traffic overhead of a shared bus and improves the performance of a bridge communication.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.41 no.12
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• pp.1914-1924
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• 2016

In this paper, considering virtualized Evolved Packet Core(vEPC) network for 5G mobile network, we propose architecture for supporting Service Function Chaining(SFC) in 5G mobile network. Using SFC in 5G network, dynamic path configuration and providing network services based on subscriber and traffic information. SFC technology provides logical ordered set of network functions and delivers packet through providing logical path over the physical network. Based on the perspective of 5G core network in distributed manner, we design hierarchical SFC architecture to manage SFC for global path including vEPC and SGi-LAN network, and internal path between virtualized network functions in each cloud. In this paper, we define architecture and call flow for establishing data path using SFC. Finally, we design testbed architecture for real implementation based on open source software.

• Journal of Korean Society of Steel Construction
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• v.22 no.2
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• pp.151-160
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• 2010

The number of cases of collapsed plastic greenhouses in farmlands has increased due to the heavy local snowfall caused by extraordinary atmospheric phenomena. Consequently, the economic losses of farmers have also increased. However the government policy in relation to damage pretension is insufficient and collapse case is repeated every year. The main reason for frame collapse is that the moment capacity of a steel pipe is not sufficient to resist a heavy snowload. In this study, experiments were conducted on the current frame system of a greenhouse with a tension tie. The frame consisted of two sections(${\phi}25.4{\times}1.5$, ${\phi}31.8{\times}1.5$), and its span length was 6.5 m. A temporary tension tie using a steel wire and a fabric rope was connected to the two joints, to which a curved beam and a straight column were connected. The pretension force was applied at the tension tie, and a vertical force simulating snowfall was applied until failure. The fabric rope frame increased the load-carrying capacity by 10-45% compared to the normal frame without a tension tie, and the steel wire frame increased the load-carrying capacity by 58-73% compared to the normal frame without a tension tie. Steel wire was found to be more effective as far as strength is concerned, but its connection details and pretension application are more difficult and complicated than those of the fabric rope. The test results thus show that the fabric rope is more preferable.

• Korean Journal of Cognitive Science
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• v.13 no.2
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• pp.1-13
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• 2002

This Paper is concerned with the impact of linguistic markers of coherence, such as causal connectives. repetitions. and anchoring devices. on the comprehension of a scientific text in Korean. A scientific text on the process of lightning formation was selected. and two versions of the text were constructed by varying the strength of coherence. Eighty-two undergraduate students took Part in the experiment in which they were instructed to fill in the blanks in each text in a recall and a recognition task and to respond to a set of question in a comprehension test. The results of this experiment revealed a selective effect of the cohesive markers. It was found that the different linguistic signals seem to Play a facilitating role in varying degrees in accordance with the type of tasks involved Moreover an analysis of topic continuity from the beginning paragraphs through the last revealed that the text was better understood in the paragraphs containing the main topic better than those without it. This finding seems to indicate that the off-line processing of scientific text is not influenced solely by the local bottom-up processing alone The effect of topic continuity seems to suggest that a global. top-down processing effect has an important role to play. overriding the impact of cohesive devices.

• Journal of the Korean Society of Radiology
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• v.13 no.6
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• pp.825-830
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• 2019

A detector module measuring a depth of interaction was developed using silicon photomultiplier (SiPM) and two layers of scintillation crystal array treated with multiple reflectors. When reconstructing an image based on a signal obtained by using different types of reflector of each layer, the interaction positions of scintillation pixels and gamma rays could be tracked by utilizing the feature that all scintillation pixels were recorded at different positions. The bottom layer uses a specular reflector, and the top layer uses a diffuse reflector to differently process the size of the signal obtained from the SiPM. The optical grease was used to recude the sharp refractive index change between the layers of scintillator and the SiPM. The signals obtained from the 16 SiPMs were reduced to four signals using the Anger equations, and the images were reconstructed using them. All the scintillation pixels composed of the two layers appeared in the reconstructed image, which distinguished the layer where the scintillation pixels and gamma rays interacted. If the detectors, which measure the interaction depth of two layers using different reflectors, will be applied to preclinical positron emission tomography, the degradation of spatial resolution appearing outside the field of interest could be solved.

• The Korean Journal of Mycology
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• v.23 no.1 s.72
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• pp.61-70
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• 1995

The genus Armillaria is important because they produce Gastrodia tubers. Seventy two isolates of Armillaria were obtained from fruit bodies grown on decayed wood in Korea. Twenty four isolates from Pinus koraiensis were identified as A. ostoyae. Two isolates from G. elata growing in the field were identified as A. mellea. Seven isolates from Acer ginnala and Quercus spp. were identified as A. tabescens. Thirty nine isolates were identified as A. gallica. Armillaria gallica was isolated from Quercus spp., Ainus japonica, Vitis amurensis and Prunus sargentii. Armillaria spp. isolates were divided into four groups based on the cultural characteristics. Group II (A. gallica KNU-A110) was better than the other groups for mycelial growth and rhizomorph formation. Isolate KNU-A110 proved to be good for production of G. elata tubers. This fungus forms mycelial fan in the plant tissue and rhizomorphs in contact with G. elata tubers. Gastrodia spp. was found in thirteen sites in Kangweon province in Korea. The plants were divided into three different kinds based on stem color. Plants with stems of brownish orange and greyish yellow were identified as G. elata, and those with greyish green colored stems were identified as G. gracilis. Gastrodia was collected mainly from humus soils rich in leaf debris, and slopes facing south from mid-May to mid-July. Once the new tubers are formed from the ancestry tuber, the ancestry tuber begins to decay. The offspring tuber, apparently gaining nutrients through rhizomorphs, begins to grow in length and slowly to enlarge. It takes three years for the offspring tuber to become ancestry tuber.

• Clean Technology
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• v.21 no.3
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• pp.141-152
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• 2015

As environmental issues are emerging, bio-plastic suppliers in leading countries have been foreseeing the strong needs for environment-friendly materials such as eco-packing materials due to increased attention and regulation on recycle. To catch up with the demand, various types of bio-plastics based on natural feedstocks were developed and released on a market. These bio-plastic products drew the great attention even in domestic industries. At present, international oil price fluctuation and heavy charge on waste raise the unit cost of production and disposal expense of conventional plastic materials. These conditions make bio-plastic an alternative, because it is not restrained by oil prices and problem in the disposal. It is also expected that bio-plastic will be applied to various types of products including containers, industrial supplies, disposables, and medical supplies. However, the bio-plastic is still in its infancy, thus more research and understanding should be followed to put it to application. Bio-plastic is considered as environment-friendly material with high potential which has the advantages of production and disposal.

• Journal of the Korea institute for structural maintenance and inspection
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• v.24 no.6
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• pp.67-76
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• 2020

This paper reports an experimental study to evaluate the flexural behavior of concrete beams reinforced using Fe based shape memory alloy (Fe-SMA) bars. For the experiment, a concrete beam of 200mm×300mm×2,200mm was produced, and a 4% pre-strained Fe-SMA bar was used as a tensile reinforcement. As experimental variables, type of tensile reinforcement (SD400, Fe-SMA), reinforcement ratio (0.2, 0.39, 0.59, 0.78), activation of Fe-SMA (activation, non-activation), and joint method of Fe-SMA bar (Continuous, welding, coupler) were considered. The electric resistance heating method was used to activate the Fe-SMA bar, and a current of 5A/㎟ was supplied until the specimen reached 160℃. After the upward displacement of the specimen due to the camber effect was stabilized, a three-point flexural loading experiment was performed using an actuator of 2,000 kN capacity. As a result of the experiment, it was found that the upward displacement occurred due to the camber effect as the Fe-SMA bar was activated. The specimen that activated the Fe-SMA bar had an initial crack at a higher load than the specimen that did not activate it. However, as with general prestressed concrete, the effect of the prestress by Fe-SMA activation on the ultimate state of the beam was insignificant.

• Korean Journal of Heritage: History & Science
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• v.45 no.1
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• pp.16-33
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• 2012

Maehwa blossom(梅花) has been favoured in literary and artistic works in the East Asia as one of representing symbols of virtuous men's character. Maehwaseookdo(梅花書屋圖) is one of major forms of painting. This paper starts from the birth of Maehwaseookdo since it aims to examine the following points: its structural origin of the Gurimaehwachonsado(九里梅花村舍圖) style; how this style was distributed in Korea; process and features of Maegamdo(梅龕圖). The current academic world admits Maehwaseookdo is originated from an ancient story of Lim Po(林逋). Even though Maehwaseookdo and Lim Po story can be linked to a meaning of schoarly hermitage, ways to structure works are hard to compare paintings based on Lim Po story. While paintings related to Limpo story such as Banghakdo(放鶴圖) and Gwanmaedo(觀梅圖) depict a scholar(s) and a few Maehwa trees with cranes, Maehwaseookdo presents scholarly hermitage with a lot of Maehwa trees which encircle a house building. As other paintings related to Maehwa blossom were widely painted since the nationwide popularity of the theme of Maehwa, Maehwaseookdo was not drown throughout the whole period of time. Since Goryeo, Maehwa paintings including Sehansamu(歲寒三友), ordinary Maehwado as one of the Four Gentlemen's plants, and Tammaedo(探梅圖) which was based on ancient anecdote of Maeng Hoyeon. Maehwaseookdo, however, was created exclusively in the 19th century. In China a similar feature took place much earlier period which was in the 17th century. Accordingly we can assume that these patterns which paintings in particular styles were generated by particular cultural phenomena. The reason why Joseon's Maehwaseookdo works were painted exclusively in the 19th century was that Kim Jeonghee's party and Sin wi had acquaintanceship with Jang Sim(張深) who got work orders for Oh Sungyang(吳嵩梁). In these corresponding activities, two types of Maehwa paintings were exchanged. In China, scholars usually drew paintings in the type of Gurimaehwachonsado(九里梅花村舍圖) depicting scenic views of Guriju(九里洲) which was riverside area under the Mt. Buchun(富春山). This place surrounded by thousands and hundreds of Maehwa trees was where Oh Sungyang(吳嵩梁) was about to retire to hermitage in. In this repect, Joseon scholars painted Maegamdo(梅龕圖) depicting a scene of a shrine with Oh Sungyang(吳嵩梁)'s poetry books surrounded by Maehwa trees for paying tribute to the wall of Maehwa trees(Maebyeok(梅癖)). This seems to adapt the format of 'Manmae(萬梅)' which appeared in the type of Gurimaehwachonsado. One of the representing works of this, is painted or supervised by Sinwi. Paintings in two types with respective meanings were combined by which was estimated to be painted by Sin Wi, then it became a structural base of by Jang Sim(張深) This type of Maegamdo brought the popularity of Maewhoseookdo which once had another name of 'Manmaeseookdo(萬梅書屋圖)' by a group of scholars such as Jo Heeyong, in the 19th century. All things considered, this paper can be a sort of precedent phrase to find out the birth of Manmaeseookdo which was very popular in the late 19th century.

• The Journal of Korean Academy of Prosthodontics
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• v.50 no.2
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• pp.92-98
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• 2012

Purpose: The aim of this study was to evaluate the effects of different abutment materials on abutment screw loosening and settling-down effect in conical connection type implant system. Materials and methods: Three types of abutment, cementation, gold UCLA, and metal UCLA abutment were used. Two UCLA groups were fabricated in a similar pattern to cementation abutment. Type III gold alloy and Nickel-Chromium alloy was used for casting gold UCLA abutment and metal UCLA abutment, respectively. Fixture and abutment were tightened to 30 Ncm by using digital torque controller and re-tightening was conducted with same force after 10 minutes. Digital torque gauge was used to measure loosening torque and fixture/abutment length was measured by digital micrometer. Dynamic loads between 25 N and 250 N were applied with $0^{\circ}$ angle to the abutment axis. After loading, fixture/abutment length was re-measured and amount of settlement was calculated. Loosening torque value was also measured for comparison Results: All three groups showed significant differences of length when comparing before and after loading, but there was no significant difference of settling amount in all groups. Loosening torque values were significantly decreased when comparing before and after loading in all groups($P$<.05). However, there was no significant difference in loss of loosening torque values when compared to groups. Conclusion: In internal conical connection type implants, dynamic load affected on settlement and loosening torque of implant, but there was no differences between abutments materials. Likewise gold UCLA abutment, metal UCLA abutment might be able to withstand functional load.