• Journal of Magnetics
• /
• v.12 no.3
• /
• pp.93-96
• /
• 2007

We investigated the electronic structure and magnetic properties of zinc-blende CrP/SrBi interface by using the all-electron full-potential linearized augmented plane wave method within the generalized gradient approximation. It is found that the half-metallicity is destroyed when the two half-metals are in contact. Magnetic moments of the atoms forming the supercell differ considerably from the respective values obtained for the bulk structures of the two materials. Cr atoms being and not being in contact with Bi atoms have magnetic moment 3.43 and $2.69{\mu}_B$, respectively. Bi atoms lose their majority electrons which results in their negative polarization. Alkaline Sr atoms are very weakly negatively polarized. The spin distribution within the supercell is such that well separated regions of positive and negative polarization are seen, especially around the layer of P atoms being in contact with the layer of Sr atoms.

• Proceedings of the KSR Conference
• /
• 2002.05a
• /
• pp.516-521
• /
• 2002

According as railway signalling equipments are computerized recently, necessity of communication protocol for interface between these equipments is increasing, Therefore the research about communication protocol structure that is need according to computerization trend of these signalling goes, especially communication protocol structure for interface between LDTS(Local Data Transmission System) and EIS(Electronic Interlocking System). Analyzed existent protocols that is applied currently for interfaces between above two signalling for this research and also technology analysis of internal/external similar protocols and operator and maker's requirement. With these study finding plain in this paper, explained summary of communication protocol structure for interface between LDTS and EIS.

• Interaction and multiscale mechanics
• /
• v.4 no.1
• /
• pp.65-83
• /
• 2011

In this study, two extreme cases of compatibility of the horizontal displacements between the foundation and soil are considered, for which the pressure and settlements of the isolated footings and member end actions in structural elements are obtained using the three dimensional models and numerical experiments. The first case considered is complete slip between foundation and soil, termed as the un-coupled analysis. In the second case of analysis, termed as the coupled analysis, complete welding is assumed of joints between the foundation and soil elements. The model and the corresponding computer program developed simulate these two extreme states of compatibility giving insight into the variation of horizontal displacements and horizontal stresses and their intricacies, for evaluation of the influence of using the interface elements in soil-structure interaction analysis of three dimensional multiscale structures supported by isolated footings.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2009.11a
• /
• pp.13-14
• /
• 2009

Intermediate Representation(IR)은 컴파일러가 Target code 를 생성하기까지의 중간 단계에서 프로그램을 표현하는 수단이다. 본 논문에서는 컴파일러의 IR을 직접 Simulation 해서 각종 profiling information을 수집하여 프로그램의 성능 향상에 도움을 줄 수 있는 IR Simulator를 제안하고자 한다. 더 나아가 IR Simulator를 위한 Data structure와 Interface는 Target Simulation에도 재사용이 가능하도록 고안되었기 때문에 재겨냥성 컴파일러의 Target Simulator를 자동으로 생성하는 연구를 진행하고 있다.

• The Journal of the Korea Contents Association
• /
• v.11 no.11
• /
• pp.79-90
• /
• 2011

The purpose of this study is to explore physical factor of digital text structure for designing e-Book interface and to develop prototype of e-Book interface by applied these factors. To address this goal, explore factor analysis and confirmatory factor analysis were employed, 237 university students were the participated in this study. According to a result, 29 items for physical feature of digital text structure were developed, 9 factors of digital text structure were also extracted; volume, depth, density, space, layout, format, signal, size, and length. Besides, to identify structure of pre-defined 9 factors, confirmatory factor analysis was conducted. As a result of CFA, the factor structure was supported by all of model fit indices.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2000.05b
• /
• pp.273-278
• /
• 2000

In order to study effects of interface layers between PZT films and electrodes for MFM(Metal-Ferroelectric-Metal) structure capacitors, we have fabricated the capacitors with the Pt/PZT/interface-layer/Pt/$TiO_2/SiO_2/Si$ structure. $PT(PbTiO_3)$ interface layers were formed by sol-gel deposition and PbO, $ZrO_2$ and $TiO_2$ thin layers were deposited by reactive sputtering. $TiO_2$ interface layers result in the finest grains of PZT films compared to $PbO_2$ and $ZrO_2$ layers. On the other hand, PT interface layers result in improved morphology of PZT films and do not significantly change ferroelectric properties. It is also observed that seed layers at the middle and top of PZT films do not give significant effects on grain size but the PT seed layer at the interface between the bottom electrode and the PZT films results in the small grain size.

• Proceedings of the Korean Vacuum Society Conference
• /
• 1999.07a
• /
• pp.29-29
• /
• 1999

The synthesis of layered structures on the nanometer scale has become essential for continued improvements in the operation of various electronic and magnetic devices. Abrupt metal-metal interfaces are desired for applications ranging from metallization in semiconductor devices to fabrication of magnetoresistive tunnel junctions for read heads on magnetic disk drives. In particular, characterizing the interface structure between various transition metals (TM) and aluminum is desirable. We have used the techniques of MeV ion backscattering and channeling (HEIS), x-ray photoemission (ZPS), x-ray photoelectron diffraction(XPD), low-energy ion scattering (LEIS), and low-energy electron diffraction(LEED), together with computer simulations using embedded atom potentials, to study solid-solid interface structure for thin films of Ni, Fe, Co, Pd, Ti, and Ag on Al(001), Al(110) and Al(111) surfaces. Considerations of lattice matching, surface energies, or compound formation energies alone do not adequately predict our result, We find that those metals with metallic radii smaller than Al(e.g. Ni, Fe, Co, Pd) tend to form alloys at the TM-Al interface, while those atoms with larger atomic radii(e.g. Ti, Ag) form epitaxial overlayers. Thus we are led to consider models in which the strain energy associated with alloy formation becomes a kinetic barrier to alloying. Furthermore, we observe the formation of metastable fcc Ti up to a critical thickness of 5 monolayers on Al(001) and Al(110). For Ag films we observe arbitrarily thick epitaxial growth exceeding 30 monolayers with some Al alloying at the interface, possible driven by interface strain relief. Typical examples of these interface structures will be discussed.

• Structural Engineering and Mechanics
• /
• v.62 no.3
• /
• pp.325-344
• /
• 2017

The present paper investigates the propagation of Love-type wave in a composite structure comprised of imperfectly bonded piezoelectric layer with lower fiber-reinforced half-space with rectangular shaped irregularity at the common interface. Closed-form expression of phase velocity of Love-type wave propagating in the composite structure has been deduced analytically for electrically open and short conditions. Some special cases of the problem have also been studied. It has been found that the obtained results are in well-agreement to the Classical Love wave equation. Significant effects of various parameters viz. irregularity parameter, flexibility imperfectness parameter and viscoelastic imperfectness parameter associated with complex common interface, dielectric constant and piezoelectric coefficient on phase velocity of Love-type wave has been reported. Numerical computations and graphical illustrations have been carried out to demonstrate the deduced results for various cases. Moreover, comparative study has been performed to unravel the effects of the presence of reinforcement and piezoelectricity in the composite structure and also to analyze the existence of irregularity and imperfectness at the common interface of composite structure in context of the present problem which serves as a salient feature of the present study.

• Structural Engineering and Mechanics
• /
• v.9 no.1
• /
• pp.69-88
• /
• 2000

A relatively simple model of a buried structure response to a surface loading that can simulate a possible opening and closure of a gap between the soil and the structure is presented. Analysis of the response of small and medium scale buried roof slabs under surface impulsive loading shows that the model's predictions are in fairly good agreement with the experimental results. Application of the model to a study case shows the relative influence of system parameters such as, the depth of burial, the arching coefficient, and the roof thickness, on the interface pressure and on the roof displacement. This model demonstrates the effect of a gap between the structure and the soil. The relative importance of including a gap opening and closure in the analysis is examined by the application of the model to a study case. This study results show that the deeper the depth of burial, the longer the gap duration, and the shorter the duration of the initial interface impact, while the higher the soil's shear resistance, the higher the gap duration, and the shorter the initial interface impact duration.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2003.05a
• /
• pp.77-81
• /
• 2003

SDM (Structural Dynamics Modification) is a tool to improve dynamic characteristics of a structure, more specifically of a base structure, by adding or deleting auxiliary (modifying) structures. In this paper, the goal of the optimal SDM is set to maximize the natural frequency of a base plate structure by attaching serially-connected beam stiffeners. The design variables are chosen as positions of the attaching beam stiffeners, where the number of stiffeners is considered as a design space. The problem of non-matching interface nodes between the base plate and beam stiffeners is solved by using localized Lagrange multipliers, which act to glue the two structures with non-matching interface nodes. As fer the cases of non-matching interface nodes problem, the governing equation of motion of a structure can be considered from the viewpoint of a topological modification, which involves the change of the number of structural members and DOFs. Consequently, the eigenpairs of the beam-stiffened plate structure are obtained by using an eigen reanalysis technique of topological modifications. Evolution Strategies (ES), which is a probabilistic population-based optimization technique that mimics the principles from biological evolution in nature, is utilized as a mean for the optimization.