• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.05a
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• pp.153-156
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• 2006

The vibration isolation system is a system that attenuates the vibration transmitted from surroundings by using external energy supply like electricity and feedback and/or feedforward functions. Such a system needs stiff structure to make precise positioning without ripple within a certain bandwidth. So, a horizontal and rotary arrangement of the actuation module is suggested by using lever linkage. Modeling and kinematic formulation are completed and system identification is accomplished to tune the design variables accurately. The vibration isolation control is performed by mu-synthesis with the uncertainties in design variables. Low frequency signal enhancement circuit and saturation proof integration algorithm are devised to use seismic sensors for displacement control. This overall system shows good disturbance rejection performance.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.48 no.4
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• pp.410-418
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• 1999

This paper describes the use of residual and parameter identification methods for fault detection in an air handling unit. Faults can be detected by comparing expected condition with the measured faulty data using residuals. Faults can also be detected by examining unmeasurable parameter changes in a model of a controlled system using a system identification technique. In this study, AutoRegressive Moving Average with seXtrnal input(ARMAX) and AutoRegressive with eXternal input(ARX) models with both single-input/single-input and multi-input/single-input structures are examined. Model parameters are determined using the Kalman filter recursive identification method. Regression equations are calculated from normal experimental data and are used to compute expected operating variables. These approaches are tested using experimental data from a laboratory's variable-air-volume air-handling-unit.

• Proceedings of the KIEE Conference
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• 1988.07a
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• pp.898-901
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• 1988

Up to now, using adaptive control method, Identification deals with system whose entire state variables and prameters are accessible for measurement. In practical situations, all the state variables cannot be measured and it is impossible to directly apply since the parameters of the system are unknown. Therefore, in this paper, using only input-output data, such a model of the system is not available since the parameters of the system are unknown. this leads to the concept of an adptive observer in which both the parameters and the state variable of the system are identified simultaniously. Lyapunov's direct method and Kalman-Yakubovich (K-Y) lemma are employed to ensure the stability of this schemes. The feature is that the signal and adaptive gain which is generated from filter is imposed upon feedback vector and then state variables and the unknown parameters can be identified. To show the usefulness of the proposed schemes, computer simulation result of unknown second-order system shows the effectiveness of the proposed schems.

• The Research Journal of the Costume Culture
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• v.7 no.6
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• pp.28-40
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• 1999

The purpose of this study was to understand the Korean teenagers\` clothing behavior through pointing out the factors that clothing behavior of teenagers that was initiated from the important reference group, TV stars. The subject of this study were 570 purposively selected students at female middle and high school students in Seoul. The results were as follows : 1. The clothing conformity to TV stars relating to demographic variables was influenced significantly by location and personal expense variable in the high school group. 2. The exhibition showed a more important role to the clothing conformity in middle school group than in high school group. 3. The clothing conformity to TV stars relating to the clothing related variables was significantly affected by self-confidence to clothing than clothing normative recognition, clothing risk recognition and degree of clothing importance regardless of groups. 4. The clothing conformity to TV stars relating to TV media variables was affected by TV media star identification variable in both groups. And in case of middle school group, interests in TV stars also had influence on the clothing conformity to TV stars. And in case of high school group, interests in TV had effect on the imitation to TV stars\` clothing. As middle school students tend to have self-identification about a particular person, TV media stars become the reference group for the adolescence to follow their clothing.

• Proceedings of the Korea Concrete Institute Conference
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• 1996.10a
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• pp.486-491
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• 1996

The purpose of present study is to propose a improved damage detection and assessment algorithm that has its basis on the method of system identification. This method allows the use of composite data which is constitute of static displacements and eigenmodes. In the dynamic test, thecurvature and slope of mode shape are introduced to formulate the error responses. The effectiveness of the proposed staristical system identification method is investigated through simulated and experimental studies. Real test data obtained from measurements are used to identify the actual location of damage and to revise the design variables in a concrete structure.

• Structural Engineering and Mechanics
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• v.63 no.6
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• pp.789-797
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• 2017

Recently, some integrated structural identification/damage detection and reliability evaluation of structures with uncertainties have been proposed. However, these techniques are applicable for off-line synthesis of structural identification and reliability evaluation. In this paper, based on the recursive formulation of the extended Kalman filter, an on-line integration of structural identification/damage detection and reliability evaluation of stochastic building structures is investigated. Structural limit state is expanded by the Taylor series in terms of uncertain variables to obtain the probability density function (PDF). Both structural component reliability with only one limit state function and system reliability with multi-limit state functions are studied. Then, it is extended to adopt the recent extended Kalman filter with unknown input (EKF-UI) proposed by the authors for on-line integration of structural identification/damage detection and structural reliability evaluation of stochastic building structures subject to unknown excitations. Numerical examples are used to demonstrate the proposed method. The evaluated results of structural component reliability and structural system reliability are compared with those by the Monte Carlo simulation to validate the performances of the proposed method.

• (The) Korean Journal of Educational Psychology
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• v.23 no.3
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• pp.543-560
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• 2009

The purpose of this study was to identify the proper identification method of the gifted students in math and science. The subjects were 6,237 students from 3rd to 7th graders. The subjects took nation-wide tests which were made for identifying the gifted students. The tests were composed of creativity, thinking skill, and academic achievement in math and science. The results of this study were as follows; First, creativity and thinking skill were positively correlated with the academic achievements. Specially, the academic achievement of science was positively correlated with the all of the sub-factors of creativity and thinking skill variables. Second, the influential power of each variable differed depending on the identification methods. Also, group 1, which was considered all variables such as, creativity, thinking skill, and academic achievement, was the most proper way to identifying the top 1% students from the subjects. These results implies the variables of creativity, thinking skill, and academic achievement have to consider identifying the gifted students in math and science.

• Journal of The Korean Association For Science Education
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• v.19 no.4
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• pp.674-683
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• 1999

The purpose of this study was to compare the ideas of pupils with that of the scientists about controlling and identifying of variables, in the two cases: open or guided inquiry. The subjects were the 7th grade boys and girls in a school, in Seoul, Korea. For the guided inquiry, the problems were given by the experiments of pupils' text. Pupils were asked to identify the variables in the experiments. For the open inquiry, pupils set their own inquiry problem. The pupils whose marks are within upper one-third of three classes were chosen. Pupils' ideas on variables were investigated in the design of experiment for their problems. In that, questionnaire developed by researchers was used. In the former, many of the pupils identify just only one variable despite of the fact there were two independent or dependent variables in the experiments. In the latter, the number of independent variables increased two or three. However, pupils do not control independent variables: they vary two independent variables simultaneously in the design of experiment. From these, we compared the pupils' ideas on variables with the scientists'

• The Journal of the Korea Contents Association
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• v.11 no.2
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• pp.385-396
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• 2011

The purpose of this study was to investigate contents identification and brand community identification on the brand community. Analysis was performed for the empirical study where important variables of this framework included attractiveness, similarity, intimacy, information quality, contents identification, and community identification, loyalty. I collected the 184 data through survey and analyzed them. The data were recorded and analyzed using the SPSS 14.0 and LSREL 8.30. The brief findings of the study were as below: Given the finding of the study, users who have contents identification directly don't affect on purchase loyalty. Therefore, company intensifies users' visiting community. Users who consistently visit community have purchase loyalty. Existing studies on online brand community is a study for the identification. This study identified the dimensions of the content attribute of the content identification and brand community identification were examined by questionnaires. Accordingly, the company operating the brand community to provide more useful suggestions.

• Journal of Global Scholars of Marketing Science
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• v.15 no.2
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• pp.27-48
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• 2005

This study analyzed the structural elements of transformational leadership on hotel employees job satisfaction and organizational identification, and inquired into how moderating variables such as demographical characteristics and the features of hotels affect transformational leadership. The ultimate purpose of this study was to provide managerial implications to hotel business operators and hotel employees. The main results of this study are as follows; According to the result of factor analysis on transformational leadership and hotel employees job satisfaction, 18 variables were derived as two factors 'obliging leadership' & 'vision leadership' factor in the area of transformational leadership, and 31 variables were derived as four factors 'welfare and work environment', 'ability display and job stability', 'colleague relationship and job performance' and 'company policy' factor. Second, stepwise regression analysis on whether the type of transformational leadership at hotels has a significant effect on employees job satisfaction & organizational identification, 'vision leadership' and job satisfaction and the both 'vision leadership' & 'obliging leadership' among the types of transformational leadership appeared to have a significant effect on hotel employees organizational identification. Third, One-Way ANOVA and t-test in order to examine significant difference in the type of transformational leadership according to demographical characteristics and general characteristics, statistically significant difference was found according to income level, the current position, work experience, the type of hotel operation and the experience of job change.