• Journal of Electrical Engineering and Technology
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• v.12 no.2
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• pp.495-501
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• 2017

The introduction of smart grid, which is an innovative application of digital processing and communications to the power grid, might lead to more and more cyber threats originated from IT systems. In other words, The Energy Management System (EMS) and other communication networks interact with the power system on a real time basis, so it is important to understand the interaction between two layers to protect the power system from potential cyber threats. This paper aims to identify and clarify the cyber security risks and their interaction with the power system in Smart Grid. In this study, the optimal power flow (OPF) and Power Flow Tracing are used to assess the interaction between the EMS and the power system. Through OPF and Power Flow Tracing based analysis, the physical and economic impacts from potential cyber threats are assessed, and thereby the quantitative risks are measured in a monetary unit.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1997.10a
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• pp.42-49
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• 1997

In this paper, the method for soil-structure interaction analyses in the time domain is proposed. The far field soil region which is the outside of the artificial boundary is modeled by using explicit frequency-dependent two dimensional infinite elements which can include multiple wave components propagating into the unbounded medium. Since the dynamic stiffness matrix of the far field soil region using the proposed infinite elements is obtained explicitly in terms of exciting frequencies and constants in the frequency domain, the matrix can be easily transformed into the displacement unit-impulse response matrix, which corresponds to a convolution integral of it in the time domain. To verify the proposed method for soil-structure interaction analyses in the time domain, the displacement responses due to an impulse load on the surface of a soil layer with the rigid bed rock are compared with those obtained by the method in the frequency domain and those by models with extend finite element meshes. Good agreements have been found between them.

• Health Policy and Management
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• v.4 no.1
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• pp.25-48
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• 1994

Noncompliance with treatment is a serious problem in the management of hypertension. We explored self-reported medication taking compliance behavior of 194 high blood pressure patients using modified health belief model hypothesizing interaction between model components. Data were collected from patients resistered hwachon community hypertension control program during February, 1993. Bivariate analysis showed perceived severity of complication, present symptom experience(p<0.05), perceived severity of hypertension and education leve(p<0.01) were significantly related to treatment experience. Logit analysis revealed that perceived severity of hypertension, perceived benefits of treatment, perceived barriers to treatment and interaction term between perceived severity of hypertension and perceived benefits of treatment contributed treatment experience. Health education from mass media was siglificantly related to continuity of treatment. We also concluded that the inclusion of interaction effects between health belief model components and the use of patient group as analysis unit lead to better study results.

• Journal of the Korean housing association
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• v.16 no.2
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• pp.55-65
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• 2005

'Movement System' is made of the interaction of user and architectural spaces related to each other in order. 'Movement' meant in movement system is possible only in the status of user and architectural space together. Movement created and disappeared by the user is not subordinated to the existing architectural space but becomes the main element of formating movement system. It is required that movement conception applied to architecture should be derived from the essence of movement and this study presents the movement system. To explain the formating process of movement system, A. N. Whitehead's process philosophy theory is at the basis and transformed in architectural aspects. On basis of these theoretical backgrounds, the process of making movement system can be explained. There are unit movement, unit object, and elements for movement process as the basic requirements for movement system, each unit is apprehended by individual operation and the nexus is composed by associative operation of apprehended units. This nexus becomes the object of a new subject and forms multiple nexus. Relation of unit movement and unit object and nexus are apprehended as the continuation and extensive continuum is made. At that time, movement with multiple phases set inbetween systems and extended multiplied. Through above study, movement system is applied to Korean traditional houses.

• Interaction and multiscale mechanics
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• v.3 no.4
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• pp.321-331
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• 2010

A new technique is proposed for bridge structural damage detection based on spatial wavelet analysis of the time history obtained from vehicle body moving over the bridge, which is different from traditional detection techniques based on the bridge response. A simply-supported Bernoulli-Euler beam subjected to a moving spring-mass unit is established, with the crack in the beam simulated by modeling the cracked section as a rotational spring connecting two undamaged beam segments, and the equations of motion for the system is derived. By using the transfer matrix method, the natural frequencies and mode shapes of the cracked beam are determined. The responses of the beam and the moving spring-mass unit are obtained by modal decomposition theory. The continuous wavelet transform is calculated on the displacement time histories of the sprung-mass. The case study result shows that the damage location can be accurately determined and the method is effective.

• Proceedings of the KSPS conference
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• 2006.05a
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• pp.117-120
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• 2006

This paper examined two hypotheses. Firstly, if the first syllable of word play an important role in visual word recognition, it may be the unit of word neighbor. Secondly, if the first syllable is the unit of lexical access, the neighborhood size effect and the neighborhood frequency effect would appear in a lexical decision task and a form primed lexical decision task. We conducted two experiments. Experiment 1 showed that words had large neighbors made a inhibitory effect in the LDT(lexical decision task). Experiment 2 showed the interaction between the neighborhood frequency effectand the word form similarity in the form primed LDT. We concluded that the first syllable in Korean words might be the unit of word neighborhood and play a central role in a lexical access.

• Proceedings of the Korean Institute of Building Construction Conference
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• v.y2004m10
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• pp.59-63
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• 2004

In recent days. it is necessary to find environment-friendly way of diposing industrial waste and reclying system. So this study will analyze the property of Porous concrete improved by concrete waste powder and recycled lightweight aggregate and then suggest the ways of reclying. The method deals with experimenting unit weight of capacity. thermal conductivity, compression and ultrasonic pluse velocity. Considering the relation between ultrasonic pluse velocity and unit weight & thermal conductivity through the graph. the result of relation between ultrasonic pluse velocity and unit weight & thermal conductivity on the graph expessed their high interaction shown as direct proportion on the graph. Recycled Porous concrete merits lightweight and adiabatic. Therefore. we will expect that the current using ALC and Recycled Porous concrete has be similar thermal conductivity.

• Speech Sciences
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• v.13 no.2
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• pp.35-46
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• 2006

This study investigated whether there are differences between Korean-English bilingual and Korean monolingual children on phonological awareness skills. Participants were 11 Korean-English bilingual children and 12 Korean monolingual children. The children's ages ranged between 6 and 7 years. The results were as follows. First, the bilingual children significantly outperformed monolingual children on overall phonological awareness tasks. The bilinguals performed significantly higher than monolinguals on all three types of phonological awareness tasks (segmentation, deletion, and blending). Second, there was a significant difference between the groups with respect to phonological units of the tasks. The bilinguals performed significantly better than monolinguals on the phonemic unit tasks, but two groups did not differ significantly on syllabic unit tasks. There was an interaction effect between unit size(syllables and phonemes) and group (bilinguals and monolinguals). Third, there were correlations for both bilingual and monolingual children between overall phonological awareness skills and word recognition skills.

• Journal of the Korea Society for Simulation
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• v.16 no.4
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• pp.33-41
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• 2007

Service-Oriented Architecture(SOA) define the interaction method between two computing entities that one entity performs a unit task instead of another entity. This, unit task, is called "Service" and interaction of these services should have independency and loosely coupled task. The effect of SOA's main functions such as loosely coupled task and independent interoperability with influence the possibility of flexible message communication between different way and different users. In this article, we analyzed the performance about system stabilization between general web service and SOA based application that implemented through WCF based messaging framework using .NET Framework and integrated data presentation method. As the result of test, we confirmed that SOA environment using WCF have more advantages.

• Bulletin of the Korean Chemical Society
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• v.31 no.8
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• pp.2247-2254
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• 2010

The surface structures of copper phthalocyanine (CuPc) thin films deposited on sulphur-passivated and plane perylene-3,4,9,10-tetracarboxylic dianhydride (PTCDA)-covered InAs(100) surfaces have been studied by low energy electron diffraction (LEED) and van der Waals (vdW) intermolecular interaction energy calculations. The annealing to $300^{\circ}C$ and $450^{\circ}C$ of $(NH_4)_2S_x$-treated InAs(100) substrates produces a ($1{\times}1$) and ($2{\times}1$) S-passivated surface respectively. The CuPc deposition onto the PTCDA-covered InAs(100) surface leads to a ring-like diffraction pattern, indicating that the 2D ordered overlayer exists and the structure is dominantly determined by the intermolecular interactions rather than substrate-molecule interactions. However, no ordered LEED patterns were observed for the CuPc on S-passivated InAs(100) surface. The intermolecular interaction energy calculations have been carried out to rationalise this structural difference. In the case of CuPc unit cells on PTCDA layer, the planar layered CuPc structure is more stable than the $\alpha$-herringbone structure, consistent with the experimental LEED results. For CuPc unit cells on a S-($1{\times}1$) layer, however, the $\alpha$-herringbone structure is more stable than the planar layered structure, consistent with the absence of diffraction pattern. The results show that the lattice structure during the initial stages of thin film growth is influenced strongly by the intermolecular interactions at the interface.