• Journal of the Korean Crystal Growth and Crystal Technology
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• v.20 no.1
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• pp.25-29
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• 2010

Thulium oxide-doped barium titanate ceramics for MLCCs with perovskite structure were prepared by a sintering process at $1320^{\circ}C$ for 2 h in a reduced atmosphere. The effect of $Tm_2O_3$ addition on dielectric property of barium titanate ceramics has been studied in terms of their microstructures. Moreover, the phase identification of the dielectric specimens was conducted to define the secondary phase (pyrochlore). The specimen doped with 1 mol% $Tm_2O_3$ exhibited the highest dielectric constant. However, the dielectric constants of specimens with more than 2 mol% $Tm_2O_3$ to $BaTiO_3$ were the lower values than that of 1 mol% doped one. The grain size and the formation of pyrochlore phase associated with the dielectric properties were examined through morphology development and the structural analysis. Furthermore, these data were compared with the property of the dielectric material doped with $Er_2O_3$. It could be concluded that the dielectric property of ceramic capacitors were attributed to the change of pyrochlore phase and the tetragonality of $BaTiO_3$ with doping.

• Journal of the Korea Computer Industry Society
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• v.7 no.3
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• pp.245-252
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• 2006

Estrangement hierarchical by bipolarization is deepened and time space that social welfare by graying corresponds great so. Specially, is real condition that indifference by patient's increase which is solitary life string is come to involve by social Voblem. Together, Jaetaek bone fracture patient's ratio is zooming. <중략>Supersonic waves operation frequency used on both end because do 1mHz, 1.3mHz, supersonic waves origination that have 1.5mHz's Piezo-ceramic crystal tranducer material each 4 premature senilitys in this research, and outside diameter according to impedance and Phase d used Gakgak4mm, 5.4mm, Dukke0.5mm, transformer deuce of length 70mm. Manufactured, and investigated supersonic waves distribution chart by capacity 50m W. Supersonic waves used by diagnosis mainly but is seen to become convenient medical treatment mounting in bone fracture patient's treatment if supplement clinically. If supplement system furthermore, is going to apply to osteoporosis patient, and this research tried to design poetic theme width directly and study rain standardization special qualify and approach basic form because do modelling.

• Proceedings of the Korean Magnestics Society Conference
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• 2007.05a
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• pp.44.2-44.2
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• 2007

• Proceedings of the Optical Society of Korea Conference
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• 2002.07a
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• pp.248-249
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• 2002

The gaseous molecular condensation retardation by laser excitation has been known, but with limited success. Condensation inhibition between the gas phase molecules by laser excitation was clearly shown in many experiments.(1)-(2) However, surface condensation inhibition of the excited molecules has been controversial for the last several decades.(3)-(4) In 1994, S. J, Sibener and Y. T. Lee published an experimental evidence of the internal energy dependence of the surface condensation of gaseous $SF_{6}$ and $CCl_4$ molecules. (omitted)

• Proceedings of the KIEE Conference
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• 1988.11a
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• pp.294-297
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• 1988

THIS PAPER IS PROPOSED A NOVEL FLUX OBSERVER BASED ON GOPINATH REDUCED ORDER OBSERVER FOR VECTOR CONTROL OF INDUCTION MOTOR. WE SUGGEST RESULT OF SIMULATION ON THE PAPER. WE WILL CONSTRUCT FLUX VECTOR FEEDBACK CONTROL TYPE FOR INDUCTION MOTOR USING FULX OBSERVER.

• 한국초전도학회:학술대회논문집
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• 2009.07a
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• pp.83-83
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• 2009

• Macromolecular Research
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• v.15 no.5
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• pp.465-468
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• 2007

• Journal of Korean Society for Quality Management
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• v.27 no.3
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• pp.94-112
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• 1999

It is booming to use computer and information owing to the information society. As software applications have grown, so too has the importance of software quality. Therefore, software quality measurement and evaluation are necessary to satisfy the users who are using computers. The ISO/IEC 9126 defines six quality characteristics and twenty-one subcharacteristics including forty inter quality characteristics. We developed software measurement and evaluation technique using the check list in accordance with the ISO/IEC 9126 in design phase. We applied idea and concept of Total Quality Management in order to evaluate and measure the quality of software. Namely, it is the concept such as "you should do it right the first time." or "you have to build quality in the process." We executed the quantitative evaluation of software, also had shown the distinctive result in order that users and developers can find the errors easily. We evaluated the quality of academic softwares in order to verify developing technique at S college. As a result of the evaluation, this college has found it necessary to maintain the software as soon as possible because academic systems are not adequate for users at this present time.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.58 no.3
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• pp.334-338
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• 2009

In this paper, We report the miniaturization of superconducting microwave power dividers based on lumped element equivalent circuits. To do this, we analyzed a conventional branch-type power divider by using an ABCD matrix under even and odd mode excitation. Then, we calculated each lumped element impedance throughout this analysis of a transmission line matrix. Also we simulated our equivalent circuits made of lumped elements by using a full wave analysis, em Sonnet. Our deign of microwave power divider based on simulated results was fabricated on high-$T_c$ superconducting thin films deposited on MgO substrate. Experimental results were reported in terms of bandwidth, center frequency, and phase difference between $S_{21}$ and $S_{31}$. We confirm that our design will be useful in the future microwave power systum.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.3
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• pp.1131-1143
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• 2016

Differential detection schemes do not require any channel estimation, which can be employed under user mobility with low computational complexity. In this work, a soft-input soft-output (SISO) differential detection algorithm is proposed for amplify-and-forward (AF) over time-varying relaying channels based cooperative communications system. Furthermore, maximum-likelihood (ML) detector for M-ary differential Phase-shift keying (DPSK) is derived to calculate a posteriori probabilities (APP) of information bits. In addition, when the SISO is exploited in conjunction with channel decoding, iterative detection and decoding approach by exchanging extrinsic information with outer code is obtained. Finally, simulation results show that the proposed non-coherent approach improves detection performance significantly. In particular, the system can obtain greater performance gain under fast-fading channels.