• The Transactions of the Korean Institute of Electrical Engineers
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• 제40권4호
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• pp.394-401
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• 1991

B-spline function is generally used for an image interpolation because of its smoothness and continuity, but it accompanies a large amount of blurring effect. In this paper, a space-variant B-spline interpolation function is proposed through deblurring process followed by de-aliasing process. The proposed function has parametric expression and performs smoothing and edge-enhancement adaptively in the interpolation process according to local property of the image. Application of this function to image enlargement, rotation, and curve representation producted good results. Even in the presence of noise, noise smoothing effect as well as edge-enhancement were observed in the image interpolation process.

• Journal of the military operations research society of Korea
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• 제27권2호
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• pp.134-148
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• 2001

In this paper, air-defense simulation model, called "DADSim", will be introduced. DADSim(Distributed Air Defense Simulation Model) was developed by Modeling&Simulation Lab of K.N.D.U.(Korea National Defence Univ) Weapon Systems Department. This model is an analysis-purpose model in the engagement-level. DADSim can simulate not only the global air-defense or Korean Peninsula but also the local air-defense or a battle field. DADSim uses the DTED(digital terrain elevation data) LeveII it for the representation of peninsula terrain characteristics. The weapon systems cooperated in the model are low/medium-range missile systems such as HAWK, NIKE, SAM. DADSim was designed in the way of object-oriented development method, implemented by C++ language. The simulation view is an event-sequenced object-orientation. For the convenience of input, output analysis, GUI(Graphic User Interface) of menu, window, dialog box, etc. are provided to the user, For the execution of DADSim, Silicon Graphic IRIX 6.3 or high version is required. DADSim can be used for the effectiveness analysis of­defence systems. Some illustrative examples will be shown in this paper.

• Wind and Structures
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• 제34권1호
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• pp.1-14
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• 2022

In this work the flow through a hollow porous 5:1 rectangular cylinder made of perforated plates is numerically investigated by means of 2D URANS based simulations. Two approaches are adopted to account for the porous surfaces: in the first one the pores are explicitly modeled, so providing a detailed representation of the flow. In the second one, the porous surfaces are modeled by means of pressure jumps, which allow to take into account the presence of pores without reproducing the flow details. Results obtained by using the two aforementioned techniques are compared aiming at evaluating differences and similarities, as well as identifying the main flow features which might cause discrepancies. Results show that, even in the case of pores remarkably smaller than the immersed body, their arrangement can lead to local mechanisms able to affect the global flow arrangement, so limiting the accuracy of pressure jumps based simulations. Despite that, time-averaged fields often show a reasonable agreement between the two approaches.

• Journal of the Korean Society for Precision Engineering
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• 제12권6호
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• pp.145-151
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• 1995

The first-order Taylor series expansion can be evaluated analytically from the formulated symbolic nonlinear dynamic equations. A closed-form linear dynamic euation is derived about a nominal trajectory. The state space representation of the linearized dynamics can be derived easily from the closed-form linear dynamic equations. But manual symbolic expansion of dynamic equations and linearization is tedious, time-consuming and error-prone. So it is desirable to manipulate the procedures using a computer. In this paper, the analytic linearization is performed using the symbolic language MATHEMATICA. Two examples are given to illustrate the approach anbd to compare nonlinear model with linear model.

• Journal of the Korean Society for Precision Engineering
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• 제14권9호
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• pp.116-123
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• 1997

We have already presented the constraint satisfaction algorithm which could solve the closed loop porblem in constraint network by using local constraint propagation, variable elimination and constraint modularization. With this algorithm, we have implemented a knowledge-based system (intelligent CAD) for supporting machine design interactively. In this paper, we present newer constraint satisfaction algorithm which can solve inequalities or under-constrained problems in constraint network, interactively and effi- ciently. This algorithm is a hybrid type of using both declarative description (constraint representation) and optimization algorithm (Simulated Annealing), simultaneously. The under-constrained problems are represented by constraint networks and satisfied completely with this algorithm. The usefulness of our algorithm will be illustrated by the application to a gear design.

• Communications of the Korean Mathematical Society
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• 제39권1호
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• pp.11-30
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• 2024

3-Lie algebras are in close relationships with many fields. In this paper we are concerned with the study of 3-Hom-Lie super algebras, the concepts of 3-Hom-Lie coalgebras and how they make a 3-Hom-Lie superbialgebras, we study the structures of such categories of algebras and the relationships between each others. We study a super twisted 3-ary version of the Yang-Baxter equation, called the super 3-Lie classical Hom-Yang-Baxter equation (3-Lie CHYBE), which is a general form of 3-Lie classical Yang-Baxter equation and prove that the superbialgebras induced by the solutions of the super 3-Lie CHYBE induce the coboundary local cocycle 3-Hom-Lie superbialgebras.

• Journal of the Korea Academia-Industrial cooperation Society
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• 제19권3호
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• pp.46-51
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• 2018

This study is one of a series of studies exploring the locality of Jeju architecture, in which we focused on the works of domestic architects, rather than those of famous foreign architects, as well as on the locality of the phenomenological aspect rather than the conceptual one, so as to reveal the locality in the present situation. It was revealed that the architects had the following viewpoints with regard to the local characteristics of Jeju: first, the hermeneutic aspect of the locality is the architectural application of the traditional Jeju architecture; second, the phenomenal aspect of the locality involves respect for the landscape and natural scenery of Jeju. There are two main ways in which architects can realize the locality that they envisage. The hermeneutic representation of Jeju would be as a locality consisting of traditional houses. The architects mainly wanted to implement the elements of the private houses through the space layout. The phenomenal representation of the locality would require them to respect the landscape and scenery of Jeju and to implement them in its architecture. This was the case if the landscape or landscape elements were directly borrowed from the buildings, or if the buildings respect the scenery or landscape of Jeju.

• Korean Institute of Interior Design Journal
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• 제23권3호
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• pp.48-55
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• 2014

Luis Barragan is a representative Mexican architect. He designed architectural space as a local architect in consideration of the Mexico's harsh Mediterranean climate. His manifestation of the regionality can be found mainly in his precise expression of light. Such method and concept of using light in Barragan's architecture made a huge impact on later architects but detailed studies on this issue have not been made actively. Hence, this paper intended to suggest a starting point or an orientation by illustrating the characteristics of using and expressing light in architecture through his cases of housing works. The study method was as follows. First, the general characteristics of light were identified by analyzing the elements of architectural space that dealt with light and the characteristics of expressing light shown in the architectural space. Second, the architectural background of Luis Barragan and the architectural space elements of the light expressed in his architectural space were extracted to form a hypothetical ground. Third, five of his works on the houses in his prime (after the year of 1945) were analyzed to explore the characteristics of relational representation between light and the architectural space elements in his architecture. Through this process, it was learned that, in his architectural works, light was the embodiment of the location-related, time-based, daily and illusionary experience into architecture. In addition, meditative light could be experienced by contrasting the soft and dispersed light and shadow of the inside space of Barragan's houses with the strong external light. Therefore, through the process above, this study is hoped to provide an opportunity for the contemporary architects of our era to rethink the fundamental correlation between architecture and light.

• The Journal of Korean Institute of Communications and Information Sciences
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• 제19권6호
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• pp.1095-1106
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• 1994

This paper presents a method for determining optimal grayscale function processing(FP) morphological filters under the least square (LMS) error criterion. The optimal erosion and dilation filters with a grayscale structuring element(GSE) are determined by minimizing the mean square error (MSE) between the desired signal and the filter output. It is shown that convergence of the erosion and dilation filters can be achieved by a proper choice of the step size parameter of the LMS algorithm. In an attempt to determine optimal closing and opening filters, a matrix representation of both opening and closing with a basis matrix is proposed. With this representation, opening and closing are accomplished by a local matrix operation rather than cascade operations. The LMS and back-propagation algorithm are utilzed for obtaining the optimal basis matrix for closing and opening. Some results of optimal morphological filters applied to 2-D images are presented.

• Journal of Korean Academy of Nursing
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• 제47권1호
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• pp.14-24
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• 2017

Purpose: The purpose of this study was to construct and test a hypothetical model of self-management in patients with hemodialysis based on the Self-Regulation Model and resource-coping perspective. Methods: Data were collected from 215 adults receiving hemodialysis in 17 local clinics and one tertiary hospital in 2016. The Hemodialysis Self-management Instrument, the Revised Illness Perception Questionnaire, Herth Hope Index and Multidimensional Scale of Perceived Social Support were used. The exogenous variable was social context; the endogenous variables were cognitive illness representation, hope, self-management behavior, and illness outcome. For data analysis, descriptive statistics, Pearson correlation analysis, factor analysis, and structural equation modeling were performed. Results: The hypothetical model with six paths showed a good fitness to the empirical data: GFI=.96, AGFI=.90, CFI=.95, RMSEA=.08, SRMR=.04. The factors that had an influence on self-management behavior were social context (${\beta}=.84$), hope and cognitive illness representation (${\beta}=.37$ and ${\beta}=.27$) explaining 92.4% of the variance. Self-management behavior mediated the relationship between psychosocial coping resources and illness outcome. Conclusion: This research specifies a more complete spectrum of the self-management process. It is important to recognize the array of clinical resources available to support patients' self-management. Healthcare providers can facilitate self-management through collaborative care and understanding the ideas and emotions that each patient has about the illness, and ultimately improve the health outcomes. This framework can be used to guide self-management intervention development and assure effective clinical assessment.