• Proceedings of the Korean Geotechical Society Conference
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• 2003.03a
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• pp.309-314
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• 2003

Impact Echo method has been successful in detecting a variety of defects in concrete structure. This study has the objectives to show important aspects of applying the Discrete Wavelet Transform(DWT) to signal processing of Modified Impact Echo(ModIE) Measurement systems and to the understanding of the seismic wave propagation. The data of ModIE were processed by DWT and compared with the results of conventional ModIE Analysis. Although it is inconsistent in the evaluated thickness of concrete lining, the DWT provides the features of separation, synthesis and de-noising in the original signal. The application of technique by wavelet was explained numerically with ABAQUS and performed experimentally with a real scale model in this work. Further works on the possible ways for creating new mother wavelet are specially needed for the enhancement of seismic signal analysis.

• Journal of the Korean Ceramic Society
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• v.49 no.4
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• pp.352-362
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• 2012

This paper explores the use of a variety of carbon nanoparticles to impart electrical, thermal conductivity, good frictional properties to silicon nitride matrices. We used the highly promising types of carbon as carbon nanotubes, exfoliated graphene and carbon black nanograins. A high-efficiency attritor mill has also been used for proper dispersion of second phases in the matrix. The sintered silicon nitride composites retained the mechanical robustness of the original systems. Bending strength as high as 700 MPa was maintained and an electrical conductivity of 10 S/m was achieved in the case of 3 wt% multiwall carbon nanotube addition. Electrically conductive silicon nitride ceramics were realized by using carbon nanophases. Examples of these systems, methods of fabrication, electrical percolation, mechanical, thermal and tribological properties are discussed.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2000.11a
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• pp.153-156
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• 2000

In this paper, a mathematical model of a permanent-magnet synchronous motor (PMSM) is derived, and the steady-state characteristics of this system, when subject to constant input voltages and constant external torque, are formulated. It is shown that the PMSM model can exhibit a variety of chaotic phenomena, under some choices of system parameters and external inputs. Based on TS fuzzy modeling methodology, the TS fuzzy model of the PMSM chaotic system is presented, so the interaction between fuzzy system and chaos can be explored, and then fuzzy-model-based control methodologies can be used to control chaos in chaotic systems. Computer simulations show that the strange attractors in the derived TS fuzzy system and original chaotic system are topologically equivalent.

• Journal of the Korean Home Economics Association
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• v.41 no.9
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• pp.43-54
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• 2003

The purpose of study is to survey the system of the Korean Gangsin-mu shaman costume and its formative character and to fine out the traditional follow patterns of government officials' attires and Po's meaning of it. The overall shape of variety 'Po's in modern times are similar to the traditional ones, but they differ greatly in size, detail color, and ornamental design. The sleeves have slits in the armholes, which can allow the hands to be drawn out easily. In addition, the knot buttons are used in the modern costumes. They are based on different formation skills from those of the traditional The original color of the shaman's costume is not their taste in color but symbolic, modern costumes color show the shaman's taste in color. This change mean a more accentuated visual effect than incantatory meaning. Another reason for color change is also the costume's material. A kind of constituent element uses synthetic fiber in modern times.

• Proceedings of the KSRS Conference
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• 1999.11a
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• pp.421-424
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• 1999

The purpose of this study is to demonstrate a variety of methods for reducing the speckle noise content of SAR images, whilst at the same time retaining the fined details and average radiometric properties of the original data. In order to increase the accuracy of classification, Two categories of filters are used (speckleblind(simple), Speckle aware(intelligent)) and Segmentation of highly speckled radar imagery is achieved by the use of the Gaussian Markov Random Field model(GMRF). The problems in applying filtering techniques to different object types are discussed and the GMRF procedure and efficiency of the segmentation also discussed.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.3
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• pp.491-497
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• 2007

As dispersed generators was driven in condition interconnecting with utility, it could cause a variety of new effects to the original distribution system that was running as considered only the one-way power flow. Therefore, the protection devices that is builted in distribution system should be designed to be able to operate with disposing of not only a fault of the generator, but also utility condition. Especially, the fault of the feeder interconnected with Dispersed Generator can cause the islanding phenomenon of open DG(Dispersed Generators). This phenomenon has many problems such as a machinery damage, electricity qualify degradation and a difficulty of the system recovery. In the fault therefore, we must separate Dispersed Generator from the system quickly. In this paper, for the fault classification of the interconnected DG and the outside feeder we judge the fault of the interconnected DG and the outside feeder in HMI through data provided by IED(Intelligent Electronic Device) on the network and decide whether it operates or not by sending the result to each relay.

• Korean Institute of Interior Design Journal
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• no.17
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• pp.203-209
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• 1998

Various living spaces have been attempted in modern resident life. basement and garre's function spaces are ignored even though they have essential environmental elements which are perceived instinctively by people. This is a good example of how rigid rough flows of interior space block the variety of living spaces. The primary purpose of this paper is to show the way of linking between whole living spaces and its parts to make better practical use of our living spaces. And I try to find out what is the original concept of he basement and garret and its relation with our residence how we use then in these days and what is the good way of practical use as our part of living space.

• Proceedings of the Korean Institute of Interior Design Conference
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• 2006.05a
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• pp.145-149
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• 2006

China which has 960km of domain area is one of the biggest countries in the world. Also China has a large population of 1,300,000,000 which are 25% of total world population and consist of 56 ethnic groups. In addition, History of China is immemorial and Confucianism of feudalistic and Taoism idea have effect on Chinese for a long time and architecture is influenced by them. Thus a large degree of variety, abundance, and uniqueness can be found in Chinese traditional dwelling. This research will be focusing on Sanapwon, a traditional housing in Beijing, which represents China's original and distinctive dwelling features. By looking at Sanapwon, we can learn the distinguishable characteristics of Chinese residential area and understand the concept of space. By looking closely at the worldly outlook, historical view, originality, and the spatial notion centered around human beings, many types of Sanapwon and its formation process have been examined Likewise indoor plane construction, and basic element of composition of space will help to study the whole of residing space.

• 보존과학연구
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• s.29
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• pp.45-64
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• 2008

'No-An-Dang' in 'Un-Hyeun palace' was using as a guesthouse by 'dea-won-goon' built in 1864. 'No-An-Dang tablet' exhibited in 'No-An-Dang' seems to be made by using the letters which were written by 'Choo-sa Kim Jeong-Hee'. This tablet was manufactured by special processes; wood frame which was made of a Korean white pine was drawn patterns by variety pigment and latticed inside are joined with 3 of horizontal square wooden sticks and 7 of vertical square wooden sticks, then several sheets of the paper mulberry put on this frame and sheets cut along the edge of letter attached lastly. This structure of tablet could cause more conservation problems than only made in wooden structures. Therefore, replica was made and exhibited in bad condition and original one kept in museum storage for effective conservation of artefacts.

• Proceedings of the Korea Concrete Institute Conference
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• 1999.04a
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• pp.721-726
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• 1999

Diverse strengthening methods for reinforced concrete are applied to real structures with a variety of materials. On the other hand, only external prestressing is used for strengthening damaged prestressed concrete girders. But the end brackets for external prestressing are hard to design and to manufacture, the magnitude of prestressing is limited when applied to real structures. The current end brackets are not clearly understood in load transmitting mechanisms and they may damage the original girder by drilling during construction. And also the designed welding area of the current bracket is insufficient to support the high load. The problems of current end bracket are solved in this study. And a new and improved end bracket is proposed and tested. The tested end bracket is similar to the end bearing bracket, but many supportting plates are addded to increase its welding length of the weakest point of the bracket. The increased welding length finally increases its load carrying capacity significantly.