• Journal of the Earthquake Engineering Society of Korea
• /
• v.21 no.5
• /
• pp.227-236
• /
• 2017

This study reviews concepts, theories and formulas included in standards on soil-structure interaction and also shows practical example of application for engineers. Real structures are 3 dimensional and multi degree of freedom but they are often idealized to single degree of freedom for convenience. In this study, detailed procedures to calculate soil spring constants and damping coefficients and method to model soil-structure system are explained. Additionally, case studies to judge fixed base condition and evaluation of applicability of simple analysis method based on response spectra are performed.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.20 no.7
• /
• pp.2108-2117
• /
• 1996

The purpose of this paper is to investigate the influence of the exciter attached for the measurement of natural frequencies when extracting the frequency response functions of the test structure in experimental modal analysis. The procedure is first to model the attached exciter as an additional degree of freedom system and next to verify the suggested model by experimentally extracting the natural frequencies of the test structure with various values of exciter mass, stinger stiffness and attachment position of the exciter on the test structure. It is concluded that as additional degree of freedom system which includes the natural frequency of the exciter itself and axial stiffness of stinger should be considered to quantatively define the coupling effects of structure-exciter interaction on the measured natural frequencies. It is not the mass of the exciter itself but the coupling effect of the additional degree of freedom mass-spring system consisting of exciter body and armature coil that characterizes the natural frequency deviation. Therefore, when the natural frequency of this additional mass-spring system is outside of the test frequency range, the coupling effect of structure-exciter interaction can be minimized.

• Journal of Korean Society of Rural Planning
• /
• v.15 no.1
• /
• pp.47-59
• /
• 2009

The aim of this study is to analyze the green-tourism centrality considering spatial interaction using Gravity Model and social network method. The degree centrality and prestige centrality were applied as green-tourism centrality index. The rural amenity resources and human resources were counted as attraction factors, and a distance among villages was used as friction factor in gravity model. The weights of rural tourism amenity resources were calculated using the analytic hierarchy process(AHP) method and applied to evaluate green-tourism potentiality. The distance was measured with the shortest path among villages using geographic information system(GIS) network analysis. The spatial interaction from gravity model were employed as link weights between nodal points; a pair villages. Using the spatial interaction, the degree-centrality and prestige-centrality indices were calculated by social network analysis and demonstrated possibility of developing integrated green-tourism region centered on high centrality villages.

• The Journal of Korean Association of Computer Education
• /
• v.17 no.4
• /
• pp.69-78
• /
• 2014

This study aims to investigate better predictors, among learner participation and interaction, for collective self-efficacy and achievement in a web-based collaborative learning environment. Interaction requires communication among two or more learners, while participation does not. In this study, interaction was measured by in-degree centrality and out-degree centrality based on the social network analysis perspective. Multiple regression analysis results from 53 college students who performed team project via online showed that in-degree centrality predicted collective self-efficacy and out-degree centrality predicted achievement, while participation was not a significant predictor.

• Journal of the Korea Society of Computer and Information
• /
• v.14 no.11
• /
• pp.213-219
• /
• 2009

This study is that internal members of social welfare are divided into the first organization directly controlling and managing subjects and the second organization supporting and assisting the first one, and both organizations are analyzed through the empirical study about cooperation degree on the basis of interaction degree related with cooperation relationship from interorganizational relationship theories. That is because organic cooperation between both sides is essential element to effectively approach the ultimate purpose which subjects and related people need because of the social welfare business. This result suggests that both sides broadly recognize the need about cooperation between management systems and that it must come first to establish values and behaviors about the cooperation among the persons in charge on the organizational internal level for organic cooperation between organizations.

• Journal of computational fluids engineering
• /
• v.21 no.1
• /
• pp.72-77
• /
• 2016

In this study, effects of thurster axis tilting angle on the thruster-hull interaction and propulsion performance in a dynamic positioning system of offshore plant are numerically investigated. Straight and 7-degree tilted downward thruster models as a form of ducted propeller are considered. For numerical simulations, Reynolds averaged Navier-Stokes equations with SST turbulence model are solved by using STAR-CCM+. Results show that thruster-hull interaction is reduced in 7-degree tilted thruster model with lower vortex strength between thruster and hull bottom, although the propulsion performance does not have noticeable difference in a bollard condition.

• Korean Parent-Child Health Journal
• /
• v.19 no.1
• /
• pp.25-32
• /
• 2016

Purpose: The purpose of this study was to use the social network analysis to verify the relationship between the interpersonal disposition and interactive characteristics of nursing college students. Five classes, a total of 117 nursing students were included in the study. Methods: The study interaction network centralization, density and in-degree & out-degree centrality were used as indicators for measuring students' study interaction. Also, the students' interpersonal disposition was measured using verified tool. Results: The results indicated that the ordinary type which gave and took the information generally showed the highest proportions in the study interaction network. Also, the empathic-acceptable tendency of social relation domain showed the highest proportions in the interpersonal disposition. Moreover, the students who play the isolate and the carrier role in the study interaction network had no relation with the expression tendency, and the transmitter role play students had no relation with the role tendency. Conclusion: Based on the results, the tutors should consider the students' interpersonal relationship disposition when implementing the instructional strategy in PBL curriculum.

• Journal of Digital Convergence
• /
• v.12 no.11
• /
• pp.57-69
• /
• 2014

This Study analyzed empirically how do brand value components of consumer perception side effect on receptive degree of product in extension types of vertical brand extension, and how does the difference of receptive degree among products of extension types be showed under the positive effect of brand value. First, brand awareness has positive effect on upward and downward extension, and receptive degree of product is higher in downward extension than upward extension. Second, brand association doesn't have positive effect on upward extension but has positive effect on downward extension. Third, perceived quality showed similar results to brand awareness. Only, receptive degree of upward extension product in high perceived quality is higher than in high brand awareness or in high brand association. Fourth, examining about interaction effect among brand value components, interaction effect between brand awareness and brand association exists in downward extension, interaction effect between brand awareness and perceived quality exists in upward and downward extension, and interaction effect between brand association and perceived quality exists in upward and downward extension. By this interaction effect, the difference of receptive degree among products of extension types grows larger.

• Yonsei Medical Journal
• /
• v.63 no.8
• /
• pp.724-734
• /
• 2022

Purpose Hereditary parkinsonism genes consist of causative genes of familial Parkinson's disease (PD) with a locus symbol prefix (PARK genes) and hereditary atypical parkinsonian disorders that present atypical features and limited responsiveness to levodopa (non-PARK genes). Although studies have shown that hereditary parkinsonism genes are related to idiopathic PD at the phenotypic, gene expression, and genomic levels, no study has systematically investigated connectivity among the proteins encoded by these genes at the protein-protein interaction (PPI) level. Materials and Methods Topological measurements and physical interaction enrichment were performed to assess PPI networks constructed using some or all the proteins encoded by hereditary parkinsonism genes (n=96), which were curated using the Online Mendelian Inheritance in Man database and literature. Results Non-PARK and PARK genes were involved in common functional modules related to autophagy, mitochondrial or lysosomal organization, catecholamine metabolic process, chemical synapse transmission, response to oxidative stress, neuronal apoptosis, regulation of cellular protein catabolic process, and vesicle-mediated transport in synapse. The hereditary parkinsonism proteins formed a single large network comprising 51 nodes, 83 edges, and three PPI pairs. The probability of degree distribution followed a power-law scaling behavior, with a degree exponent of 1.24 and a correlation coefficient of 0.92. LRRK2 was identified as a hub gene with the highest degree of betweenness centrality; its physical interaction enrichment score was 1.28, which was highly significant. Conclusion Both PARK and non-PARK genes show high connectivity at the PPI and biological functional levels.

• Bulletin of the Korean Chemical Society
• /
• v.18 no.9
• /
• pp.1010-1013
• /
• 1997

Nucleophilic substitution reactions of (Z)-phenylethyl (X)-benzenesulfonates with (Y)-pyridines were investigated in acetonitrile at 60 ℃ under respective pressures. The magnitudes of the Hammett reaction constants, ρX, ρY and ρZ indicate that a stronger nucleophile leads to a greater degree of bond formation of C-N and a better leaving group is accompanied by a less degree of bond breaking. The magnitude of correlation interaction term, ρij can be used to determine the structure of the transition state (TS) for the SN reaction. As the pressure is increased, the Hammett reaction constants, ρX and |ρY|, are decreased, but correlation interaction coefficient, ρXZ and |ρYZ|, are increased. The results indicate that the reaction of (Z)-phenylethyl (X)-benzenesulfonates with (Y)-pyridines probably moves from a dissociative SN2 to early-type concerted SN2 mechanism by increasing pressure. This result shows that the correlation interaction term ρij can be useful tool to determine the structure of TS, and also the sign of the product ρXZ·ρYZ can be predict the movement of the TS.