• 대한금속재료학회지
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• 제46권9호
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• pp.585-592
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• 2008

Flip-chip bonding using Cu-Sn mushroom bumps composed of Cu pillar and Sn cap was accomplished, and the contact resistance and the thermal cycling reliability of the Cu-Sn mushroom bump joints were compared with those of the Sn planar bump joints. With flip-chip process at a same bonding stress, both the Cu-Sn mushroom bump joints and the Sn planar bump joints exhibited an almost identical average contact resistance. With increasing a bonding stress from 32 MPa to 44MPa, the average contact resistances of the Cu-Sn mushroom bump joints and the Sn planar bump joints became reduced from $30m{\Omega}/bump$ to $25m{\Omega}/bump$ due to heavier plastic deformation of the bumps. The Cu-Sn mushroom bump joints exhibited a superior thermal cycling reliability to that of the Sn planar bump joints at a bonding stress of 32 MPa. While the contact resistance characteristics of the Cu-Sn mushroom bump joints were not deteriorated even after 1000 thermal cycles ranging between $-40^{\circ}C$ and $80^{\circ}C$, the contact resistance of the Sn planar bump joints substantially increased with thermal cycling.

• ETRI Journal
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• 제27권1호
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• pp.122-125
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• 2005

A polymer-based planar-lightwave-circuit-type variable optical attenuator (VOA) was fabricated using a hot embossing process. With an optimized one-step embossing process, forty micro-channels for the guidance of light were defined on a polymer thin film with an accuracy of ${\pm}0.5{\mu}m$. The fabricated polymeric thermo-optic VOA shows 30 dB attenuation with 110 mW electrical input power at $1.55{\mu}m$. The rise and fall times are less than 5 ms.

• ETRI Journal
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• 제32권6호
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• pp.837-842
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• 2010

This paper proposes robust source localization methods for estimating the azimuth angle, elevation angle, velocity, and range using a low-complexity planar antenna array in impulsive non-Gaussian noise environments. The proposed robust source localization methods for wireless communication applications are based on nonlinear M-estimation provided from Huber and Hampel. Simulation results show the robustness performance of the proposed robust methods in impulsive non-Gaussian noise.

• 한국광학회:학술대회논문집
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• 한국광학회 2009년도 동계학술발표회 논문집
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• pp.233-234
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• 2009

The theoretical study of a surface-plasmon wave at a planar metal-chiral interface is presented in this communication. It is found that a surface-plasmon wave can be excited at the planar interface of a thin metal film and a structurally dielectric chiral medium, if the exciting plane wave is P-polarized.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.127-129
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• 2006

In this paper, a synchronous permanent magnet planar motor (SPMPM) with Halbach array is proposed for its high energy density. The magnetization and flux density distribution are obtainedby magnet scalar potential the characteristics such as inductance, back-EMF and thrust are evaluated. It can be concluded that the analysis of SPMPM with Halbach magnet array is credible and feasible.

• Journal of applied mathematics & informatics
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• 제10권1_2호
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• pp.27-40
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• 2002

For two integers m, n with m $\leq$ n, an [m,n]-factor F in a graph G is a spanning subgraph of G with m $\leq$ d$\_$F/(v) $\leq$ n for all v ∈ V(F). In 1996, H. Enomoto et al. proved that every 3-connected Planar graph G with d$\_$G/(v) $\geq$ 4 for all v ∈ V(G) contains a [2,3]-factor. In this paper. we extend their result to all 3-connected locally finite infinite planar graphs containing no unbounded faces.

• 대한수학회지
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• 제48권6호
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• pp.1143-1152
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• 2011

The existence of periodic solutions for the planar Hamiltonian systems with positively homogeneous Hamiltonian is discussed. The asymptotic expansion of the Poincar$\acute{e}$ map is calculated up to higher order and some sufficient conditions for the existence of periodic solutions are given in the case when the first order term of the Poincar$\acute{e}$ map is identically zero.

• Journal of applied mathematics & informatics
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• 제26권3_4호
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• pp.511-517
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• 2008

Let G be a planar graph. It is proved that if G does not contain a k-cycle with a chord for some k ${\ni}$ {4,5,6}, then G is total-($\Delta(G)+2$)-colorable.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2004년도 전력전자학술대회 논문집(2)
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• pp.677-681
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• 2004

This paper presents the design and implementation of a low-profile power supply developed for AC-PDP application systems. In the proposed power supply, planar magnetics and SMD devices are integrated into advanced power conversion techniques to implement a low-profile power supply applicable to most AC-PDP application systems. Engineering details on the design and fabrication of planar magnetic components are presented. The performance of the prototype power supply is also demonstrated to validate the application potentials of the proposed power supply.

• 대한전자공학회논문지
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• 제26권11호
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• pp.1658-1665
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• 1989

Reactor design considerations over several critical parameters for a planar type reactive ion etcher are given. The etch uniformity is taken as a principal design constraint. The characteristics of economicaly available vacuum pumping system are taken as practical design constraints. A set of theoretical conditions on the chamber geometry and on the gas delivery and vacuum system, that satisfy the design constraints, are derived from basic properties of RF glow discharge and gas dynamics. The theoretical results are applied to decide design parameters of a practical single-wafer-per-chamber planar type reactive ion etching machine.