• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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• pp.178-178
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• 2012

Neutral atom temperature was measured by Laser Rayleigh scattering method using neutral depletion by neutral heating with ideal gas law in Inductively coupled plasma. We observed sudden pressure change when plasma is turned on and off. We analyzed mechanism of neutral heating by employing zero-dimensional neutral and ion energy balance model simultaneously. The results showed that neutral atom temperature increase with ion density. The mechanism of neutral atom heating and cooling is mainly dominated by ion-neutral collision including elastic and charge-exchange collision and by wall cooling respectively.

• The Korean Journal of Ceramics
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• 제6권3호
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• pp.280-285
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• 2000

The electrolyte, $(HO)_2C_6H_2(SO_3Na)_2H_2O $(Tiron), disperses efficiently alumina powder in aqueous media and stable suspensions with 60 vol% solid loading can be prepared. The strong adsorption of this additive is mainly due to the ability of the molecule to form chelate rings with the particle surface but electrostatic interactions between the surface charge and the anionic dispersant strongly influence the amount of Tiron adsorbed. By using a cationic exchange route to substitute the counter ion which neutralizes the sulfonate groups, new molecules of dispersant have been prepared, either with mineral cations as $Li^+,\; Na+^,\; NH_4^\;+$, or with organic cations as counter ion but organic counter ions lead to less to less viscous suspensions than $Na^+$ in particular when the number of carbon atoms of the aliphatic chain increases from 1 to 3.

• KDI Journal of Economic Policy
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• 제40권3호
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• pp.69-89
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• 2018

We study whether a default option attached to non-recourse mortgages improves borrowers' surplus from mortgage financing. By defaulting on mortgage debt, borrowers can save their non-collateralized income from being foreclosed. In exchange, borrowers must forgo non-monetary surplus from retaining any collateral. Banks may charge a high mortgage rate due to increased default rates. We find that the interest rate of non-recourse mortgage decreases with the borrower's surplus from home ownership. Moreover, non-recourse mortgages benefit only borrowers who deem housing property as an investment asset. Hence, the transition to a non-recourse mortgage is detrimental to welfare if the borrower enjoys a large surplus from home ownership. Although the borrower privately knows how much surplus she enjoys from home ownership, a menu of non-recourse mortgage contracts may exist, yielding a separating equilibrium without information rent.

• Journal of Magnetics
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• 제10권2호
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• pp.71-75
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• 2005

An effective method, i.e., the solid atom method, is suggested to obtain the Coulomb interaction parameter, U, and the Hund exchange coupling constant, J, for use in the LDA+U calculation. The par~meters are obtained self-consistently during the LDA+U calculation. The method is applied to typical transition metal oxides and $MnB^{VI}(B^{VI}=S,Se,Te)$. The U values for the transition metal oxides have similar magnitude to previous calculations although they are obtained by a much simpler method. $MnB^{VI}s$ have been characterized as crossroads materials between charge transfer and band insulators by the LDA+U calculation.

• 대한화학회지
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• 제39권9호
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• pp.722-727
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• 1995

순환 전압-전류법으로 합성한 폴리아닐린 막의 전기화학적 임피던스 측정을 0.1M 황산용액에서 수행하였다. 전기 전도성을 갖는 퍼텐셜 영역에서 전하-이동 정항은 낮은 값을 나타냈으며, 따라서 교환 전류밀도는 큰 값으로 측정되었다. 고분자의 축전 용량은 이중층 축전 용량보다 크게 나타났으며 이값은 전극 퍼텐셜에 따라 변하였다. 측정된 임피던스 데이터로부터 전극의 등가 회로를 추정하였으며, 이 등가 회로를 토대로 하여 폴리아닐린 막대에서 혼입된 이온의 물질 이동 파라미터를 산출하였다.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 2002년도 동계연구발표회 논문개요집
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• pp.94-95
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• 2002

Recently, we have seen a rapid advance in the evolving field of spin electronics (or spintronics). In spintronics, some feasibilities of new electronic applications utilizing spin degree of freedom have been explored. Diluted magnetic semiconductors (DMSs) are premising materials for spintronics because they have both charge and spin degree of freedom in a single substance. DMSs are refereed to semiconductor alloys in which some atoms are randomly substituted for by magnetic atoms. (omitted)

• 한국막학회:학술대회논문집
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• 한국막학회 1997년도 춘계 총회 및 학술발표회
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• pp.21-22
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• 1997

최근의 이온교환막은 종래의 양이온교환막의 표면에 polycation 등의 얇은 층을 덧붙인 다층막(multi-layer membrane)의 형태가 많이 이용되고 있으며, 정전기적 반발력의 차 등을 이용하여 원자가가 다른 이온들간의 투과성에 차를 부여하기 위하여 이용되고 있다. 이 때문에 polycation막을 통한 1가 이온과 2가 이온의 투과성을 연구하는 것은 우수한 이온교환막을 제작하는것 이상으로 중요하다. 본 연구에서는 고정전하농도(fixed charge density, $\Phi$ X)가 낮은 다공성 저전하음이온교환막을 제작하여, 양측에 대이온(counterion)은 같고 복이온(co-ion)이 다른 전해질용액을 두었을 경우에 관찰되는 막전위를 측정하였다. 이를 토대로 음이온교환막을 통한 막전위의 농도의존성에 관하여 검토하였으며, 비평형열역학(non-equilibrium thermodynamies)에 기초한 이론적 모델을 도입하여 실험치와 비교, 해석하였다.

• 대한전기학회논문지:전력기술부문A
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• 제54권4호
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• pp.193-198
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• 2005

As the electrical power industry is restructured, the electrical power exchange is extended. One of the key information used to determine how much power can be transferred through the network is known as available transfer capability (ATC). To calculate ATC, traditional deterministic approach is based on the severest case, but the approach has the complexity of procedure. Therefore, novel approach for ATC calculation is proposed using cost optimization in this paper Cheju Island interconnected HVDC system with mainland in KEPCO (Korean Electric Power Corporation) systems, and the demand of Cheju Island increases about 10 ($\%$) every year. To supply for increasing demand, the supply of HVDC system must be increased. This paper proposed the optimal transfer capability of HVDC system between Haenam in mainland and Cheju in Chju Island through cost optimization. The cost optimization is considered production cost in Cheju Island, wheeling charge through Haenam-Cheju HVDC system and outage cost with one depth (N-1 contingency)

• 한국표면공학회지
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• 제29권5호
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• pp.407-414
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• 1996

We have investigated the effects of H atoms on thin film growth processes and surface reactions. In the oxidation of Si, Si surfaces are passivated against the $O_2$ adsorption by terminating dangling bonds with H atoms. Moreover, the existence of Si-H bonds on Si(100) surfaces enhances the structural relaxation of Si-O-Si bonds due to a charge transfer from Si-Si back bonds. In the heteroepitaxial growth of a Si/Ge/Si(100) system, H atoms suppress the segregation of Ge atoms into Si overlayers since the exchange of Ge atoms with Si atoms bound with H must be accompanied with breaking of Si-H bonds. However, 3-dimensional island growth is also promoted by atomic H irradiation, which is considered to result from the suppression of surface migration of adsorbed reaction species and from the lowering of step energies by the H termination of dangling bonds.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2012년도 전력전자학술대회 논문집
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• pp.134-135
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• 2012

This paper analyzes the characteristics of the power system of Jeju island in 2014, which has wind farms with the support of BESSs (Battery Energy Storage Systems). In the simulation, the electrical loads are predicted based on Korea Power Exchange's data and the wind turbines are considered with new installed plans within 2014. The situation that some wind farms are forced to disconnect from the grid instantaneously is considered. The BESSs are controlled by using SOC (State of Charge) and power smoothing control algorithm. The simulation results show the effectiveness of the proposed method.