• Journal of applied mathematics & informatics
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• v.18 no.1_2
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• pp.361-376
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• 2005

Optimality conditions are derived for a nonlinear fractional program in which a support function appears in the numerator and denominator of the objective function as well as in each constraint function. As an application of these optimality conditions, a dual to this program is formulated and various duality results are established under generalized convexity. Several known results are deduced as special cases.

• 대한예방의학회:학술대회논문집
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• 2004.10a
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• pp.46.2-47
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• 2004

• The Transactions of the Korean Institute of Electrical Engineers
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• v.37 no.3
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• pp.180-185
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• 1988

This paper considers the problem of the optimal input design for parameter estimtion in the ARMAX model in which the system and noise transfer function have the common denominator polynomial. Deriving the information matrix, in detail, for the assumed model structure and using the autocorrelation functin of the filtered input as design variables, it is shown that D-optimal input signal can be realized as an autoregressive moving average process. Computer simulations are carried out to show the standard-deviation reduction in the parameter estimtes using the optimal input signal.

• Lingua Humanitatis
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• v.1 no.1
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• pp.3-11
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• 2001

This article maintains that language not only connects the domains of objectivity and subjectivity but simultaneously occupies its own autonomous realm and creates the two domains as well. This means that the role of language in recognizing things in the universe is more important than we usually think, and that the system of language exists independently of the human thinking and objective reality. In this respect, study of language stands as a core subject in humanities, making itself a common denominator for full understanding of philosophy, theology, history, psychology, and arts.

• Proceedings of the IEEK Conference
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• 2002.07c
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• pp.1875-1877
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• 2002

There exist several forms of transfer function descriptions for multivariable LTI systems. We treat transfer function matrix with characteristic polynomial as its common denominator named Characteristic Transfer-function Matrices (CTM). First, we clarify necessary and sufficient conditions of CTM, then, we show some related lemmas. These interpretations not only offer deeper explanations but they also provide ways for calculations of all possible transfer matrices, system zeros, and inverse polynomial matrices.

• Journal of the Korean Institute of Telematics and Electronics
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• v.24 no.3
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• pp.420-424
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• 1987

The model reduction methods of the linear time invariant continuous systems are proposed. The energy dispersion method is used to obtain the model denominator. And the model numerator is found by the modified residue method or the time moment matching method. The methods suggested are compared with the method suggested by Lucas and give good results.

• Journal of the Korean Society of Costume
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• v.62 no.6
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• pp.112-126
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• 2012

The style of a dress allows important characterization of an era since they reflect contemporary politics, society, culture and arts. Within a same category, period costumes develop into styles that reflect specific consciousness. The research method and the scope of the study are as follows: the research adopts a historical study method and a comparative research from a microscopic point. The scope includes resistance costumes that proceed with sans-culotte that comprises of the resistance party during the 18th French Revolution (1783-1799), and also a Hippy style which was popularized during the 1960s and 1970s for its anti-war movement. We researched both similarities and differences of design factors reflecting resisting consciousness in costumes that affected costume characteristics related to their socio-cultural background. Sans-culotte and the Hippie style reflect a common denominator in anti-social resisting customs. First, they show common characteristics that combine fashion trends of resistant element and design features. Second, they have common features which are the characteristics of deviation. On the other hand, these two customs also present a discriminative denominator in anti-social resisting customs. In the case of sans-culotte, they tend to symbolize confrontation by dividing into two equal parts: the old and new mode. Sans-culotte confronts the conventional mode and promotes practical costume styles based on justice standpoints. First, hippies pursue an exposition of individual emotions that disclose internal meanings of love and desire. Second, they focus on subjective characteristics and chase after masteries and pleasures by expressing intensity. Third, it extends and develops folk costumes from many countries that reveal ethnic trends. Therefore, this research compares and contrasts different changes in the fashions of revolutionary periods, and aims to recognize the relationship between design and costume characteristics, thus contributing to the predictions of future changes in fashion.

• The Journal of the Acoustical Society of Korea
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• v.36 no.1
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• pp.1-11
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• 2017

In this study, novel approximate form of the square-root operator of three dimensional acoustic Parabolic Equation (3D PE) is proposed using a rational approximant for two variables. This form has two advantages in comparison with existing approximation studies of the square-root operator. One is the wide-angle capability. The proposed form has wider angle accuracy to the inclination angle of ${\pm}62^{\circ}$ from the range axis of 3D PE at the bearing angle of $45^{\circ}$, which is approximately three times the angle limit of the existing 3D PE algorithm. Another is that the denominator of our approximate form can be expressed into the product of one-dimensional operators for depth and cross-range. Such a splitting form is very preferable in the numerical analysis in that the 3D PE can be easily transformed into the tridiagonal matrix equation. To confirm the capability of the proposed approximate form, comparative study of other approximation methods is conducted based on the phase error analysis, and the proposed method shows best performance.

• Journal of the Korean School Mathematics Society
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• v.25 no.4
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• pp.307-332
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• 2022

This action research was carried out to help students learn fractions computation by making and using semi-concrete fraction manipulatives that can be used continuously in math classes. For this purpose, the researcher and students made semi-concrete fraction manipulatives and learned how to use these through reviewing the previously learned fraction contents over 4 class sessions. Afterward, through the 14 classes (7 classes for learning to reduce fractions and to a common denominator, 7 classes for adding and subtracting fractions with different denominators) in which the principle inquiry learning model was applied, students actively engaged in learning activities with fraction manipulatives and explored the principles underneath the manipulations of fraction manipulatives. Students could represent various fractions using fraction manipulatives and solve fraction computation problems using them. The achievement evaluation after class found that the students could connect the semi-concrete fraction manipulatives with fraction representation and symbolic formulas. Moreover, the students showed interest and confidence in mathematics through the classes using fraction manipulatives.

• Journal of the Ergonomics Society of Korea
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• v.31 no.1
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• pp.41-48
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• 2012

Objective: Companies want to expand their business by providing their services at other devices and new services based upon existing services. Therefore, they look for building brand identity by providing same experience throughout devices and services. Background: Many services are available to use at multiple devices including mobile phones, tablet, personal computers, and televisions, thanks to proliferation of n-screen and cloud technology. Method: It was discussed that consistency, which emphasizes the regularity and has been one of essential aspects of user interface design, seems not effective to be applied to n-screen services, owing to different screen size, input and output peripherals, usage environment and users' attitude. Results: A new definition of same experience among different devices and services, called coherence, was introduced and abstraction levels of user interfaces were proposed as the denominator of defining coherence. Then types of users' task knowledge at each abstraction level were discussed with examples. Conclusion: This paper concluded by discussing design requirements for designing coherent user interfaces among devices and services.