• Proceedings of the Korean Society for Quality Management Conference
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• 2009.10a
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• pp.80-88
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• 2009

As well as the development of the measurement of service quality, various kinds of service measurements are also being developed. Especially the mobile telecommunication service being representative to the mobile telecommunication company would be the mostly developed area. Its development can be understood along with the development of the telecommunication companies as well as cellular companies, not only the service alone. It is a differentiated phenomenon in the current research, such as the organic influence between the service quality and product. Of course there are such products placed on sale and enjoyed the common service, but at present there is another case that the product is on the market exclusively with the mobile company in here. This paper make a suggestion about process to improve how to make a new product include of customers view. So. This paper was using the QFD and AHP.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2008.04a
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• pp.294-297
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• 2008

This is the study to investigate the Algorithm of BRI 2002 which is high level estimation program of smoke movement and phenomenon for performance based of design named 'ROOT C', made by Japan. BRI2002 is composed of 3 parts, one is main program, and the others are 4 subroutines and blockdata. The aim of this study is to analyze the BRI 2002, the only one certified program for the P.B.D and compare the other common program for smoke movement simulation program.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1997.04a
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• pp.621-626
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• 1997

Combustion instability is a common phenomenon in a ducted flame burner and is known as accompanying low frequency oscillation. This is due to the interaction between unsteady heat release rate and sound pressure field, that is, thermoacoustic feedback. In Rayleigh criterion, combustion instability is triggered when the heat additions is in phase with acoustic oscillation. A Rijke type burner with a pre-mixed flame is built for investigating the effect of Reynolds number and equivalence ratio on thermoacoustic oscillation. In addition, the effect of wall temperature is presented. The results suggest that the frequency of max. oscillation is dependent on Reynolds number and equivalence ratio whereas its magnitude is not a strong function of these two parameters. On the other hand, the wall temperature distribution has much strong effects on the oscillation, even creates different mode of acoustic resonance.

• Proceedings of the KSR Conference
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• 2009.05a
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• pp.959-965
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• 2009

To meet the demand increasing passengers in railway vehicles, railway transportation service companies are increasing the numbers of cars per train-set. Two solutions, Variable train-set formations and Multiple train-set operation, are common way to increase the transportation capability. These kind of long distance train-set can effect train-set command and control system, and sometimes the digital signals using train line from master cabin can not reach to the systems located the other extremity slave car. This is so called Voltage Drop. This phenomenon is originated from the electrical power consumption and electrical cable resistance, and cause to the equipments or cars located end of the electrical cable way, malfunction or abnormal operations. This voltage drop happens not only in train lines but also Battery Power Lines. The purpose of this investigation is to design high reliability railway vehicles by clarifying the possibility of happening these events case by case, by analyzing the reasons, and finally by finding the best solutions.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2007.10a
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• pp.300-301
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• 2007

In this study, it is investigated that sheet characteristics of high strength steel sheets and effect of springback. High strength steel sheets has got attention in automobile industry of high strength and high formability. Springback is a common phenomenon in sheet metal forming, caused by the elastic recovery of the internal stresses after removal of the tooling. However, the information in deformation behavior of high strength steel sheets, including bending and sheet characteristics and springback, is not enough until now. In this research, the V-bending experiment and analysis have been done to obtain the information of springback of high strength steel sheets. Tensile test for high strength steel sheets was done to got tensile properties of elastic modulus and flow stress of the material. It analyzed springback according to the sheet characteristics with using roll-forming model. FE-Simulation used DEFORM-$3D^{TM}$.

• Journal of Korea Society of Digital Industry and Information Management
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• v.9 no.1
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• pp.141-150
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• 2013

This study proposes technology using Active Shape Model to track the object separating it by depth-sensors. Unlike the common visual camera, the depth-sensor is not affected by the intensity of illumination, and therefore a more robust object can be extracted. The proposed algorithm removes the horizontal component from the information of the initial depth map and separates the object using the vertical component. In addition, it is also a more efficient morphology, and labeling to perform image correction and object extraction. By applying Active Shape Model to the information of an extracted object, it can track the object more robustly. Active Shape Model has a robust feature-to-object occlusion phenomenon. In comparison to visual camera-based object tracking algorithms, the proposed technology, using the existing depth of the sensor, is more efficient and robust at object tracking. Experimental results, show that the proposed ASM-based algorithm using depth sensor can robustly track objects in real-time.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09b
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• pp.1209-1210
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• 2006

A novel sintering process is proposed for bonding of $BaTiO_3$ and $Al_2O_3$ layers. Common commercial glass was used and infilterated among filler particles. As the kind of commercial glass, the phenomenon of the infilteration is different. Although Sud-1140 glass forms a glass/filler composite, it is not completely infilterated into the filler particles at $900^{\circ}C$. However as the increase of sintering temperature the infilteration of glass was improved. In this study, GA-1 and GA-12 glasses were infilterated the more than Sud-1140 glass. However, they are reacted by $BaTiO_3$ layer. The results of the experiment show that constrained sintering and the co-firing of the different materials were possible for glass infilteration using Sud-1140 glass at $1000^{\circ}C$.

• Transactions of the Korean Society of Automotive Engineers
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• v.12 no.6
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• pp.80-89
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• 2004

In order to confront the increasing air pollution and the tightening emission restrictions, this research developed a diesel engine using DME, the advanced smoke-free alternative fuel. By numerical analysis, flow field, spray, and combustion phenomenon of the DME engine was presented. Using an experimental method, the configuration of the fuel supply system and operation/power performance was tested with the current plunger pump. Most emission performance, especially smoke performance was significantly improved. The possibility of conversion from the current diesel engine into the DME engine was affirmed in this research. However, it was found that the increase of engine RPM and fuel amount need to be properly adjusted through matching the characteristics of fuel and injector for further improvement.

• Proceedings of the KSR Conference
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• 2004.10a
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• pp.1028-1033
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• 2004

The open deck steel bridge is the most common type in railway bridges. Steel I-shaped girders are connected with sleepers directly without ballast and moving train loads are transmitted directly to the girder, so this bridge has weak characteristics on impact. Therefore, considerable accelerations can cause unsatisfactory dynamic behavior of the open deck steel bridge. Especially, Impact created at rail joints can increase the dynamic response of the bridge and this phenomenon would be injurious to passenger comfort. In the present study, dynamic behavior of the open deck steel bridge which has a rail joint is estimated through experimental studies and bridge-train interaction analysis considering surface irregularities by rail joints.

• Imaging Science in Dentistry
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• v.42 no.3
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• pp.197-200
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• 2012

Gemination, a relatively uncommon dental anomaly, is characterized by its peculiar representation as a tooth with a bifid crown and a common root and root canal. It usually occurs in primary dentition. To come across gemination in a supernumerary tooth is a rare phenomenon. The purpose of this paper is to present a unique case of hyperdontia wherein gemination in an impacted supernumerary tooth resulted in a trifid crown unlike the usual bifid crown. The role of conventional radiographs as well as computed tomography, to accurately determine the morphology and spatial location, and to arrive at a diagnosis, is also emphasized in this paper.