• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.1147-1152
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• 2004

Switched Reluctance Motors have an inexpensive, intrinsic simplicity and low cost that makes them well suited to home appliance and office applications. However the motor suffering with necessity of shaft position sensor, lead to non-linearity of operations. Further, the involvement of static converters deteriorates the operational power factor. Implementation of a sensorless algorithm, can remove the need of position sensors. Also, the drive includes a compact power factor control in the input stage by implementing Zero Current Switching Quasi-Resonant Boost Technology. This paper presented, aims at optimized low line current distortion, high power factor, low cost and a shaft position sensorless Switched Reluctance Motor drive.

• Communications for Statistical Applications and Methods
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• v.8 no.1
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• pp.97-107
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• 2001

A simultaneous test criterion for multiple hypotheses concerning comparison of two multivariate normal populations is considered by using the so called Bayes factor method. Fully parametric frequentist approach for the test is not available and thus Bayesian criterion is pursued using a Bayes factor that eliminates its arbitrariness problem induced by improper priors. Specifically, the fractional Bayes factor (FBF) by O'Hagan (1995) is used to derive the criterion. Necessary theories involved in the derivation an computation of the criterion are provided. Finally, an illustrative simulation study is given to show the properties of the criterion.

• The Korean Journal of Ceramics
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• v.2 no.1
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• pp.11-18
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• 1996

The variation of electrical conductively and Seebeck coefficient of FeSi2 according to the density of the specimen has been observed over the temperature range 50 to $700^{\circ}C$. A conventional pressureless sintering method with various sintering time (0, 0.5, 1, 5h) at $1190^{\circ}C$ and/or various sintering temperatures(1160, 1175, 1190, $1200^{\circ}C$) for 2 h was carried out to prepare $FeSi_2$ specimens having various densities. The relationship between the electrical conductivity and Seebeck coefficient was investigated after two steps of annealing (at $865^{\circ}C$ and then $800^{\circ}C$ for total 160h) and thermoelectric measurement. The electrical conductivity for the specimens showed a typical tendency of semiconductor, the average activation energy of which in the intrinsic region (above $300^{\circ}C$) was observed approximately as 0.452 eV, and increased slightly with density. On the other hand, the specimen of the lower density showed the higher value of Seebeck coefficient in the intrinsic region. As the temperature fell into the non-degenerate region, the highly densified specimen which had relatively little residual metal phase showed the higher value of Seeback coefficient. The power factor of all specimens showed the optimum value at $200^{\circ}C$. However, the power factor of the specimen of the lower density increased again from $400^{\circ}C$ and that of the higher dense specimen increased from $500^{\circ}C$. The power factor was more affected by Seebeck coefficient than electrical conductivity over all temperature range.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1505_1506
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• 2009

In this paper, micro cantilevers which are made of two different materials - fused quartz and single crystalline silicon - and have similar dimensions were fabricated and their mechanical Q-factors were evaluated to compare intrinsic damping properties of those two materials. Resonant frequencies and Q-factors were measured for the cantilevers having fixed widths and thicknesses, and different lengths. The measured Q-values are in a range of 64,000 - 108,000 for fused quartz cantilevers, and 31,000 - 35,000 for silicon cantilevers, respectively. Experimental results support high Q-factors of fused quartz compared to single crystalline silicon due to its good intrinsic damping properties.

• Journal of the Korean Data and Information Science Society
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• v.12 no.1
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• pp.41-50
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• 2001

We propose the Bayesian testing for the equality of K-exponential populations means. Specially we use the intrinsic Bayesian factors suggested by Beregr and Perrichi (1996,1998) based on the noninformative priors for the parameters. And, we investigate the usefulness of the proposed Bayesian testing procedures via simulations.

• Knowledge Management Research
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• v.18 no.1
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• pp.1-24
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• 2017

The voluntary knowledge creation plays an important role in achieving competitive advantage in the organization from the perspective of knowledge management. Although many companies have introduced the Knowledge Management Systems (KMS) for this purpose, they have not gained the expected benefits from those systems. One of the reasons for that is KMS have not provided organization members with sufficient intrinsic motivation about knowledge creation, diffusion and application. Therefore, this study proposes a concept called psychological knowledge ownership as intrinsic motivation factor that facilitates knowledge creation and examines its antecedents and consequences. The research results show that reputation, self-efficacy, and expertise sharing have impacts on psychological knowledge ownership, which in turn influences knowledge creation attitude. In conclusion, we discuss both theoretical and practical implications of this research and suggest its limitations.

• Proceedings of the Korea Database Society Conference
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• 2002.10a
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• pp.3-21
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• 2002

The purpose of this study is to demonstrate individual's mobile Internet acceptance by extending the technology acceptance model (TAM) to the field of the mobile Internet. This research utilized the structural equation model to examine the research model on the mobile Internet use. System quality and information quality as external variables were examined, and playfulness as an intrinsic factor was tested. The research model was successfully validated in the environment of extension model for the mobile internet.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.185-186
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• 2005

Intrinsic gettering is usually used to improve wafer quality which is an important factor for reliable ULSI devices. The two-step annealing method was adopted in order to investigate interactions between oxygens and secondary defects during oxygen precipitation process in lightly and heavily boron doped silicon wafers with high energy $^{11}B^+$ ion implantation. Secondary defects were inspected nearby the projected range by high resolution transmission electron microscopy. Oxygen pileup was measured in the vicinity of the projected range by secondary ion mass spectrometry for heavily boron doped silicon wafers.

• Archives of Plastic Surgery
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• v.32 no.5
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• pp.656-659
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• 2005

Plantar corn is a circumscribed and sharply demarcated hard mass of traumatic hyperkeratosis, which has a central core impacting the dermis deeply and causes pain while walking. The cause of the corn is the mechanical stress to the skin induced by several causative factors; extrinsic(tight shoes) or intrinsic(bony prominence), or combined(the claw toe). We found 7 cases of patients with a painful recurrent plantar corn which had an epidermal cyst under its lesion. These corns and cysts were excised totally and there was no recurrence in all cases during two to four months follow-up period. We think that an epidermal cyst may be another intrinsic factor for the development of a plantar corn. So, an epidermal cyst should be considered once in a recurrent plantar corn to be recalcitrant against popular treatments.

• Bulletin of the Korean Chemical Society
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• v.4 no.1
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• pp.36-41
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• 1983

An equation is derived which correlates the unperturbed dimensions $_0$ of polypeptides with the helical contents in the helix-coil transition region by using a simple model of a polypeptide chain. The model is a chain of connected balls which represent the repeating units, -CO-NH-CHR-, based on the fact that the repeating unit has a plane structure. The changing trend of the expansion factor ${\alpha}_{\eta}$ in the transition region is connected with the helical content $f_H$. The intrinsic viscosities [${\eta}$] of polypeptides are calculated from the unperturbed dimensions and the ${\alpha}_{\eta}$ factors. The above calculated results concerning $_0$ and [${\eta}$] are compared with other authors' theoretical and experimental results. From the comparison, we concluded that our theory explains better the chain dimensional behavior of polypeptides in the helix-coil transition region than others.