• Proceedings of the Korea Concrete Institute Conference
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• 2004.05a
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• pp.490-493
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• 2004

In the analysis of early-age concrete behavior, the fresh concrete is considered as a structural element immediately after mixing. But for the activation of real structural behavior in the fresh concrete, the so-called setting time is necessary a few hours after the beginning of hydration reaction. In this paper, analysis on the setting behavior is carried out by proposing an analytical model based on the percolation theory as well as the expanding cluster model by defining the setting as a microstructure formation in fresh concrete. An experimental investigation is also carried out to show the influences of curing temperature, mineral admixtures and chemical admixture on setting behavior of fresh concrete. Finally, the analytical results using proposed model are compared with the experimental results for the sake of verification.

• Fashion & Textile Research Journal
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• v.13 no.1
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• pp.73-81
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• 2011

The purpose of this study was to examine the effect of consumption values on well-being attitude and the effect of well-being attitude on well-being oriented behavior. This study administered a questionnaire survey to adults between 10s and 60s who lived in Seoul, Daegu, and Kyungbuk region. Data collected from 285 respondents were analyzed by descriptive statistics, t-tests, ANOVA tests, factor analyses, and structural equation modeling (SEM). The model of the study was tested by structural equation modeling and the results of SEM revealed positive effects of social value and functional value on well-being attitude and positive effect of well-being attitude on well-being oriented behavior. The results of t-tests and ANOVA tests showed that there were significant differences in consumption values, well-being attitude, and well-being oriented behavior among marital status, age, educational level, and income level groups.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2007.04a
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• pp.393-398
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• 2007

Fatigue Behavior of a GFRP bridge deck consisting of rectangular unit modules is studied by an experimental method. The experiment focuses on how the damage in the transverse direction influence the overall behavior of the deck It is proposed filling the space in each module with a soft foam. Using the recent experimental data, the fatigue behavior is discussed. If the space of the deck is filled with the foam, the fatigue life of the deck was increased about 1,000 times for the same level of the stress variation as the reference deck not filled.

• Fashion & Textile Research Journal
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• v.10 no.3
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• pp.307-315
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• 2008

The purpose of this study was to examine the influence of purchase behavior of Cosmeceuticals according to appearance concern. The subjects of this study were 709 women aged for 20 to 50 living in Daegu. The questionnaires were conveniently sampled from December 20 to 31, 2007. The SPSS 12.0 package was use for data analysis which included Frequency analysis, Factor analysis, Cronbach's a and Analysis Structural Equation Modeling by use of Amos 5.0. The results of this study were as follows; Appearance concern had influence on usage behavior of cosmeceuticals and usage satisfaction of cosmeceuticals, but appearance concern had not influence on usage preference of cosmeceuticals. Usage behavior of cosmeceuticals had influence on usage satisfaction of cosmeceuticals and usage preference of cosmeceuticals. And usage satisfaction of cosmeceuticals had influence on usage preference of cosmeceuticals.

• Journal of the Korea institute for structural maintenance and inspection
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• v.1 no.1
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• pp.75-87
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• 1997

To study the behavior a deck when it was collide with the ship approaching to the deck to berth, it was analyzed the effect zone by the ship collision which consists of deck slab and PC piles of the quay. The numerical technique is used to simulate the behavior of the deck when the ship hit the expansion joint of deck between the deck slabs. The failure behavior and zone of the deck are determinated by the comprehensive numerical study. The impact energy by the ship is also evaluated. It is concluded that these numerical analysis gave a reasonable estimation of the remedial area of the deck damaged by ship collision.

• Journal of the Korea institute for structural maintenance and inspection
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• v.6 no.4
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• pp.129-137
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• 2002

In this study, mixed-mode fracture behavior is simulated effectively through the numerical method using the axial defomation link elements which can predict the behavior of quasi-brittle material. The behavior of quasi-brittle material is modeled numerically using the exponential tension softening constitutive equation and verified by comparing with the result of published experimental result. In order to verify the mixed-mode fracture behavior through the developed numerical method, analysis of mode I is formulated and the result is compared with those of FEM first, and then mixed-mode analysis is analyzed and compared with existing theories and experimental data. Also the characteristics of fracture behavior is examined through the analysis of crack generation with respect to various mode mixity.

• Structural Engineering and Mechanics
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• v.52 no.6
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• pp.1193-1208
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• 2014

A simulation of failures on responsible elements is only one form of the extreme structural behavior analysis. By understanding the dynamic behavior in incidental situations, it is possible to make a special structural design from the point of the largest axial force, stress and redundancy. The numerical realization of one such simulation analysis was performed using FEM in this paper. The boundary parameters of transient analysis, such as overall structural damping coefficient, load accelerations, time of load fall and internal forces in the responsible structural elements, were determined on the basis of the dynamic experimental parameters. The structure eigenfrequencies were determined in modal analysis. In the study, the basic incidental models were set. The models were identified by many years of monitoring incidental situations and the most frequent human errors in work with heavy structures. The combined load models of structure are defined in the paper since the incidents simply arise as consequences of cumulative errors and failures. A feature of a combined model is that the single incident causes the next incident (consecutive timing) as well as that other simple dynamic actions are simultaneous. The structure was observed in three typical load positions taken from the crane passport (range-load). The obtained dynamic responses indicate the degree of structural sensitivity depending on the character of incident. The dynamic coefficient KD was adopted as a parameter for the evaluation of structural sensitivity.

• Journal of the Korea institute for structural maintenance and inspection
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• v.7 no.1
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• pp.191-198
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• 2003

The pavement stiffness is scarcely used in structural analysis to design the superstructure of bridge. It is reasonable not to consider it in the case of asphalt concrete pavement over concrete deck because the pavement stiffness compared with the concrete deck plate can be ignored. However, sometimes, the pavement materials have a similar amount of elastic modulus to concrete and are applied to the orthotropic steel deck plate which has relatively less stiffness compared with the concrete deck plate. In this paper, the steel plate deck of a real bridge project was analyzed by considering the pavement stiffness by linear elastic FEM. It was assumed that a perfect bond between the steel plate deck and the pavement exited. The results indicated that the structural behavior of the orthotropic steel deck plate can be estimated enough to affect the evaluation result of structural capacity in some cases. Therefore, the investigations by experimental tests and more advanced numerical model are indispensible in figuring the design formula for considering the effects of pavement stiffness in the structural analysis of an orthotropic bridge.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2007.04a
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• pp.321-326
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• 2007

The joined-wing is a new concept of the airplane wing. The fore-wing and the aft-wing arc joined together in the joined-wing. The range and loiter are longer than those of a conventional wing. The joined-wing can lead to increased aerodynamic performances and reduction of the structural weight. The structural behavior of the joined-wing has a high geometric nonlinearity according to the external loads. The gust loads are the most critical loading conditions in the structural design of the joined-wing. The nonlinear behavior should be considered in the optimization of the joined-wing. It is well known that conventional nonlinear response optimization is extremely expensive: therefore, the conventional method is almost impossible to use in large scale structures such as the joined-wing. In this research, geometric nonlinear response structural optimization is carried out using equivalent loads. Equivalent loads are the load sets which generate the same response field in linear analysis as that from nonlinear analysis. In the equivalent loads method, the external loads are transformed to the equivalent loads (EL) for linear static analysis, and linear response optimization is carried out based on the EL.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.9
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• pp.279-291
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• 2016

The objective of this study is to determine the structural relationships among the infant's temperament, father's involvement in child-rearing, and the infant's social and emotional behavior. To this end, research was conducted with 330 parents of infants aged 1 and 2 in 55 day care centers located in J city and I city, Jeollabukdo. Frequency analysis, reliability analysis, correlation analysis, confirmatory factor analysis, and structural model equation analysis were conducted using SPSS 21.0 and AMOS 21.0. First, the results of the structural model equation analysis showed that the infant's temperament had a negative correlation with leisure and guidance, while it had a positive correlation with activity and impulsivity, which are external manifestations of their social and emotional behavior. Father's involvement in child-rearing had a negative correlation with the adaptability and mood aspects of the child's temperament, and also with general anxiety, an internal aspect of his or her social and emotional behavior. Social and emotional behavior had a positive correlation with the approach avoidance aspect of the infant's temperament. Second, according to the results of the analysis of the route between the variables, infant temperament was found to be a significant route, having a statistically negative correlation with father's involvement in child-rearing. The results of this study showed that infant's temperament and father's involvement in child-rearing had effects on the infant's social and emotional behavior, and suggested the importance of having a proper understanding of the educational implications of the father's involvement in child-rearing, in terms of its effects on the infant's social and emotional behavior.