• The Korean Journal of Ceramics
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• 제6권2호
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• pp.124-128
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• 2000

Electrical properties of $ZrO_2-TiO_2Yb_2O_3$mixed conductor (Ti-YbSZ) were investigated. This mixed conductor can be applied as a membrane for gas separation at high temperatures. The total conductivity decreased with increasing the $TiO_2$concentration. At high temperatures, the rate of the conductivity degradation became smaller than that at low temperatures. From the oxygen partial pressure dependence of the total conductivity of Ti-YbSZ, the electronic conductivity increased with increasing $TiO_2$concentration at low oxygen partial pressures and at high temperatures. Both 15 and 20 mol% $TiO_2$doped YbSZ showed high oxygen permeability. Mixed conductors, which has high $TiO_2$concentration in YbSZ, are promising materials for using as a membrane for gas separation at high temperatures.

• 대한음성학회지:말소리
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• 제52호
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• pp.133-144
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• 2004

The quality of narrowband speech can be enhanced by the bandwidth extension technology. This paper proposes a mixed excitation and an energy compensation method based on Gaussian Mixture Model (GMM). First, we employ the mixed excitation model having both periodic and aperiodic characteristics in frequency domain. We use a filter bank to extract the periodicity features from the filtered signals and model them based on GMM to estimate the mixed excitation. Second, we separate the acoustic space into the voiced and unvoiced parts of speech to compensate for the energy difference between narrowband speech and reconstructed highband, or lowband speech, more accurately. Objective and subjective evaluations show that the quality of wideband speech reconstructed by the proposed method is superior to that by the conventional bandwidth extension method.

• 전기학회논문지
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• 제61권2호
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• pp.187-193
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• 2012

Nash Equilibrium (NE) is as useful tool for investigating a participant's strategic generation quantity in a competitive electricity market. Cournot model may give a mixed strategy NE instead of a pure strategy when transmission constraints are considered. A mixed strategy is difficult to compute, complicated to understand conceptually, and hard to implement in an electricity market practically. This paper presents that a mixed strategy does not appear in Stackelberg leader-follower model even under a transmission congestion. A solution method is proposed for the leader-follower model under a nondifferentiable space of a strategy variable. Based on the pure strategy NE with a transmission line congested, the merit of leader-follower model is shown from a social welfare point of view.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.262-264
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• 2005

We propose a filter design method to suppress the effect of gyroscope mixed random errors at INS system level. It is based on the result that mixed random errors can be represented by a single equivalent ARMA model. At first step, the time difference of equivalent ARMA process is performed, which consider the characteristic of indirect feedback Kalman filter used in INS filter. Next, a state space conversion of time differenced ARMA model is achieved. If the order of AR is greater than that of MA, the controllable or observable canonical form is used. Otherwise, we introduce the state equation of which the state variable is composed of the ARMA model output and several step ahead predicts of that. At final step, a complete form state equation is presented. The simulation results shows that the proposed method gives less transient error and better convergence compared to the conventional filter which assume the mixed random errors as white noise.

• 한국디지털건축인테리어학회논문집
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• 제11권1호
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• pp.23-31
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• 2011

In order to cope with the demands of the rapidly changing society, advanced countries enrolled in OECD have been establishing corresponding directions as integrating their fields in economy, society, and education as one system. To be a part of the international changes, Korea has presented "Mixed-Use of schools and community facilities." "Mixed-Use of schools and community facilities" enables schools to expand necessary facilities, which were not secured due to insufficient budget, through community funding. Communities could not secure enough convenient facilities because they did not have enough sites for the facilities; however, school sites have made the communities possible to have facilities. As a result, the demand for "Mixed-Use of schools and community facilities" has increased. Therefore, this study redefines the concept of the Mixed-Use of School Facilities in the perspective of the main users, researches the current state of the Mixed-Use of School Facilities through case studies in Korea, and intends to research preferences of the synthesis through surveys. In addition, the study proposes the proper size and the standard of the facilities that are possible to synthesize them with schools. In the future, in running this Mixed-Use of School Facilities business, the data from this study can be utilized.

• East Asian mathematical journal
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• 제4권
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• pp.157-173
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• 1988

• 한국염색가공학회지
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• 제29권4호
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• pp.268-275
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• 2017

As the substitute of synthetic coloring materials for hair dyeing, we selected some natural ones of three primary colors such as sappan wood, logwood(red), gardenia blue(blue) and amur cork tree(yellow). Mixed colorants and metallic mordanting technique were used to widen the color space of dyed samples. In view of similarity in morphological and chemical structure, wool was adopted as the reference material for human hair to evaluate the color properties of hair dyeing. The color properties of the dyed samples were evaluated by using CIE $L^*a^*b^*$ and Munsell color systems. The addition of an alum or ferrous mordants was effective to expand the color space of hair and to increase the colorfastness to washing and light more than the rating of 1. Displaying the dyed samples by using Munsell color system, better linearity of hue values between the dyed samples of wool and human hair was shown when alum mordant was used.

• 한국실내디자인학회:학술대회논문집
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• 한국실내디자인학회 2005년도 추계학술발표대회 논문집
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• pp.143-146
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• 2005

Human activity pattern has been changed as the contemporary urban society changes. Diverse activities repeat regular patterns as time passes. Diagram is a simple drawing which aims to organize and unify various information. The elements of the social behaviour could be spatialized by means of diagram applications. By using diagrams, architects understand contemporary urban society and form new space conditions. Time-based activity patterns consists of activity pattern in a restricted space and in urban structure for space use. Activity patterns for different time zones are explained by two types of diagrams, space occupation and flexibility of space, By the characteristic of space system structred by these diagrams, activities and programs are rearranged and variety of space is allowed through flexibility. Also, programs are mixed to apply to simultaneous occurrence of ever-changing human activities.

• 터널과지하공간
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• 제31권6호
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• pp.549-560
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• 2021

쉴드 TBM(Tunnel Boring Machine) 굴진 시 TBM에 작용하는 커터헤드 토크, 추력, 챔버압, 상향력 등은 TBM의 굴진성능을 결정하는 데 매우 중요한 요소들이다. 그러나 균질한 지반 조건에 비해 복합지반을 굴진할 때 TBM에 작용하는 힘들은 그 경향이 달라 TBM 굴진성능을 저해할 수 있다. 따라서 본 연구에서는 복합지반 굴진이 TBM에 작용하는 토크, 추력, 챔버압, 상향력에 미치는 영향을 수치해석적으로 모사하고자 하였다. 해석 모델은 개별요소법(DEM, discrete element method)과 유한차분법(FDM, finite difference method)을 연계하는 방안을 적용한 TBM 굴진 모델을 사용하였다. 본 연구에서는 상부 화강풍화토와 하부 풍화암으로 구성된 복합지반을 굴진하는 것을 가정하여 굴진을 모사하였으며, 복합지반 경계면의 위치, 경사에 따라 TBM에 작용하는 힘에 대한 영향을 해석적으로 분석하였다.

• Ocean Science Journal
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• 제42권4호
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• pp.241-246
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• 2007

Northern Arabian Sea (NAS) between $17^{\circ}N-20.5^{\circ}N$ and $59^{\circ}E-69^{\circ}E$ was observed by using Argo float daily data fur about 9 months, from April 2002 through December 2002. Results showed that during April - May mixed layer shoaled due to light winds, clear sky and intense solar insolation. Sea surface temperature (SST) rose by $2.3^{\circ}C$ and ocean gained an average of 99.8 $Wm^{-2}$. Mixed layer reached maximum depth of about 71 m during June - September owing to strong winds and cloudy skies. Ocean gained abnormally low $\sim18Wm^{-2}$ and SST dropped by $3.4^{\circ}C$. During the inter monsoon period, October, mixed layer shoaled and maintained a depth of 20 to 30 m. November - December was accompanied by moderate winds, dropping of SST by $1.5^{\circ}C$ and ocean lost an average of 52.5 $Wm^{-2}$. Mixed layer deepened gradually reaching a maximum of 62 m in December. Analysis of surface fluxes and winds suggested that winds and fluxes are the dominating factors causing deepening of mixed layer during summer and winter monsoon periods respectively. Relatively big]h correlation between MLD, net heat flux and wind speed revealed that short term variability of MLD coincided well with short term variability of surface forcing.