• Wind and Structures
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• v.13 no.3
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• pp.235-256
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• 2010

The aeroelastic stability of bridge decks equipped with multiple tuned mass dampers is studied. The problem is attacked in the time domain, by representing self-excited loads with the aid of aerodynamic indicial functions approximated by truncated series of exponential filters. This approach allows to reduce the aeroelastic stability analysis in the form of a direct eigenvalue problem, by introducing an additional state variable for each exponential term adopted in the approximation of indicial functions. A general probabilistic framework for the optimal robust design of multiple tuned mass dampers is proposed, in which all possible sources of uncertainties can be accounted for. For the purposes of this study, the method is also simplified in a form which requires a lower computational effort and it is then applied to a general case study in order to analyze the control effectiveness of regular and irregular multiple tuned mass dampers. A special care is devoted to mistuning effects caused by random variations of the target frequency. Regular multiple tuned mass dampers are seen to improve both control effectiveness and robustness with respect to single tuned mass dampers. However, those devices exhibit an asymmetric behavior with respect to frequency mistuning, which may weaken their feasibility for technical applications. In order to overcome this drawback, an irregular multiple tuned mass damper is conceived which is based on unequal mass distribution. The optimal design of this device is finally pursued via a full domain search, which evidences a remarkable robustness against frequency mistuning, in the sense of the simplified design approach.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.11 no.1
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• pp.52-61
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• 2008

The purpose of this study is to investigate the children's different responses on the playground and facilities by the materials. For the study, the overall satisfaction on the playgrounds, the visiting frequency, the staying time, and olfactory and tactile responses were collected and analyzed by the materials. The materials for the playing facilities were categorized into 3 different groups ; steel, regular form wood and natural wood. The each group was also estimated and analyzed through the SD (sematic differential) scale which consisted of landscape adjectives. According the results, children liked and most highly scored the playground and playing facilities with natural wood in every items; overall satisfaction, visiting frequency, the staying time, and olfactory and tactile. On the other hand, the steel facilities were most negatively assessed in almost every items. Especially children felt the steel facilities were not environmentally friendly and very boring, comparing to the others. However, only 6 cases were analyzed in this study, because there were few playgrounds with natural wood facilities, so it is necessary to research on more cases to generalize these results.

• Journal of Digital Convergence
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• v.13 no.7
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• pp.33-45
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• 2015

Present study aims to describe who are the non-regular female workers in South Korea. The dominant form of employment of Korean female non-regular workers is characterized by instable contract, low wage, long-time work and exclusion from the state and occupational welfare. Also, non-regular female workers are not homeogenous but there are various groups of women among female non-regular workers including young part-time workers, high educational middle class contract professionals, particular contract workers such as home-schooling teachers. However, it would worth noting that over 40s, low-educational, low income, breadwinning women who are working in sales, service, and simple handy job are most likely to become non-regular female workers in South Korea. Those women are the major group among non-regular female workers. The public assistance (in cash) for non-regular workers are necessarily needed for them at this point in South Korea.

• Journal of Institute of Control, Robotics and Systems
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• v.15 no.8
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• pp.812-817
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• 2009

In this paper, a new method to design sliding surfaces using eigenstructure assignment is proposed. Most conventional methods for constructing the surfaces require special form like canonical or regular canonical form of system matrices. But the proposed method can be applied to arbitrary system matrices. Futhermore, the surface matrix, C can be decided for the matrix multiplication, CB to have a designated form. SVD is used to decide desirable eigenvectors explicitly. To verify the proposed algorithm, a sliding mode controller for a multivariable system with matched uncertainty is constructed. The controller is designed to guarantee minimum approach velocity to the sliding surface.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.162-162
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• 2012

ZnPc and CuPc molecules stacked similar way in the film, but showed different growth modes in thermal evaporation. The distribution of CuPc crystals did not change by the film thickness, whereas the distribution of ZnPc became random as the increase of the film thickness. The disc type nanograins of CuPc were quite regularly distributed at the initial growth regime and the regular distribution of nanograins was kept during the film growth. On the other hand, ZnPc consisted in ellipsoid shaped nanograins and the distribution of nanograins was not regular in the initial growth regime. The irregular distribution of nanograins changed to the regular mode at the later growth regime by showing structure factor in GISAXS measurement. The different initial nanograin distribution in ZnPc and CuPc was related to the different nanostructure in the mixed layer with C60 to form the bulk heterojunction.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.22 no.12
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• pp.1715-1725
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• 1998

A two-dimensional transient inverse heat conduction problem involving the estimation of the unknown location, ($X^*$, $Y^*$), and timewise varying unknown strength, $G({\tau})$, of a line heat source embedded inside a rectangular bar with insulated boundaries has been solved simultaneously. The regular conjugate gradient method, RCGM and the modified conjugate gradient method, MCGM with adjoint equation, are used alternately to estimate the unknown strength $G({\tau})$ of the source term, while the parameter estimation approach is used to estimate the unknown location ($X^*$, $Y^*$) of the line heat source. The alternate use of the regular and the modified conjugate gradient methods alleviates the convergence difficulties encountered at the initial and final times (i.e ${\tau}=0$ and ${\tau}={\tau}_f$), hence stabilizes the computation and fastens the convergence of the solution. In order to examine the effectiveness of this approach under severe test conditions, the unknown strength $G({\tau})$ is chosen in the form of rectangular, triangular and sinusoidal functions.

• Journal of the Korean Institute of Educational Facilities
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• v.21 no.2
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• pp.3-12
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• 2014

Elementary School is a special facility where sense of place plays critical role for the development of children. Children in special education call for special attention as they hold inferior status compared to the children in regular class especially under the inclusive education policy. Eight cases of special education class area are analyzed in terms of social space, personal space and favorite place which is known to be basic factor for the development. As a result outdoor space found to be designed inappropriate even when designed accessible to the special education class as it could not meet the developmental needs of children in special education. Special education class area inside the building is also found to be too exclusive to allow social mix with children in regular class disregarding the intention of inclusive education. Location of these class should be strategic as it is critical to be linked with regular classroom efficiently still allowing psychological buffer as the children in special education tend to form restorative space inside the special education classroom showing the possibility of creating sense of place there.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.23 no.3
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• pp.117-126
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• 2012

Objectives : We developed the short form of the Mentalization Improvement Program for Adolescent-Community Model (MIPAdo-CM-S), based on the concept of the mentalization. Methods : The MIPAdo-CM was composed of 6 sessions and was applied to 133 students in the 1st grade of a middle school for six weeks during their regular school hours. After 6 weeks, we compared the endpoint changes of Adolescent Mental Problem Questionnaire-Revised (AMPQ-R), Emotional Empathy Test, Peer Aggression Scale, Peer Bullying Scale, School Adjustment Scale, Test Anxiety Inventory and Visual Analogue Scale between the subject and the control group. Results : On the Visual Analoge Scale, students in the trial classes reported an increased understanding and respect for others, as well as themselves. Conclusion : The efficacy of MIPAdo-CM was subjective improvement of understanding and respect for both others and themselves. To prove objective usefulness of this program, further studies should be administered in the form of long-term, regular and structured courses.

• Journal of Advanced Navigation Technology
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• v.7 no.2
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• pp.180-190
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• 2003

By using accurate closed-form Green's functions obtained from real-axis integration method, the full-wave analysis of CPW discontinuities are performed in space domain. In solving MPIE(Mixed Potential Integral Equation), Galerkin's scheme is employed with the linear basis functions on the triangular elements in air-dielectric boundary. In the singular integral arising when the observation point and source point coincides, the surface integral is transformed into the line integral and the integral is evaluated by regular integration. By using the Green's function from the real-axis integration method, the discontinuities are characterized accurately.

• Journal of Fashion Business
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• v.6 no.2
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• pp.93-109
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• 2002

This study measured the accompanying rating, recall, and recognition of advertisements, which were run with different methods of spacing in the magazines. To achieve this objective the study chose a qualitative research and performed a reliable test. After the survey was completed, the advertisement recall test was performed. In addition, two days later, the recognition test was performed to the survey respondents and data on the memory of respondents on the advertisements was collected. As a result, rating, recall and recognition of the advertisement's were significantly different by the various forms of advertisements in the magazines. In the advertisement rating and recall by the advertisement printing forms, rather than the regular printing form of running the target advertisement for two pages in a role and the irregular printing form, the continuous printing form was confirmed to be more effective. In addition to that, in the form of running continuous target advertisements for six pages in a role, the effects of the advertisements recall and the recognition were increased. A continuous printing form had higher outcomes on the rating, recall and recognition of advertisements. Therefore, conclusively, it gave more effects in increasing the memory of the advertisement for the consumers. The conclusion of the study provided suggestions on the forms of advertisement to stimulate the memory of consumers in the magazine advertisement.