• 대한수학회지
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• 제45권1호
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• pp.41-61
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• 2008

We study Lorentzian surfaces with the constant Gaussian curvatures or the constant mean curvatures in the 3-dimensional Lorentzian space and their transformations. Such surfaces are associated to the Lorentzian Grassmannian systems and some transformations on such surfaces are given by dressing actions on those systems.

• Kyungpook Mathematical Journal
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• 제61권2호
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• pp.409-439
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• 2021

We consider partial matchings, which are finite graphs consisting of edges and vertices of degree zero or one. We consider transformations between two states of partial matchings. We introduce a method of presenting a transformation between partial matchings. We introduce the notion of the lattice presentation of a partial matching, and the lattice polytope associated with a pair of lattice presentations, and we investigate transformations with minimal area.

• 충청수학회지
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• 제23권2호
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• pp.315-321
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• 2010

Waring's problem deals with representing any nonconstant function in a set of functions as a sum of kth powers of nonconstant functions in the same set. Consider ${\sum}_{i=1}^p\;f_i(z)^k=z$. Suppose that $k{\geq}2$. Let p be the smallest number of functions that give the above identity. We consider Waring's problem for the set of linear fractional transformations and obtain p = k.

• 한국정보과학회논문지:소프트웨어및응용
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• 제33권1호
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• pp.138-141
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• 2006

LR 문법의 부분 클래스인 k-transformable 문법, PLR 문법, 확장된 PLR 문법은 LL 문법으로의 커버링 변환이 존재하는 클래스이다. 한편 이들 클래스에 대한 LL 커버링 변환 방법은 모두 다른 정형식에 근거하기에, 제시된 LL 커버링 변환간의 관련성은 명확하지 않다. 본 논문에서는 LL 커버링 변환에 관한 통합 모델을 제시한다. 기존 클래스에 대한 변환 방법들은 제시된 모델의 특정한 예로서 생성된다.

• Journal of information and communication convergence engineering
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• 제6권3호
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• pp.279-284
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• 2008

We propose the iconic animation of the software requirement specifications by using the object and dynamic models of the object modeling technique(OMT) methodology. In order to produce the iconic animation, we use "graphical classes" and "icon transformations." In general, the graphical classes are defined for each class of the object diagram. The icon transformations which show the activities of the application are constructed by considering the meaning of the activities and are defined by either basic or compound icons. The icon transformations are added to the state diagrams to generate extended state diagrams. The animation system generates the header files and the code instantiating GUI from the object diagram having graphical classes. The system also generates "event methods" from the extended state diagrams. When the event methods are executed, the behavior of the events is animated by the icon transformations.

• 대한기계학회논문집B
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• 제25권11호
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• pp.1467-1475
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• 2001

In the present paper, approximate coordinate transformations for simulation of turbulent flows with active wall motions, leading to a significant reduction in the computational cost while maintaining the numerical accuracy, are presented: the Navier-Stokes equations are coordinate-transformed with an approximation of Taylor-series truncation and neglect of some less-significant terms. The performance of the proposed transformations is evaluated in simulation of the channel flow at Re$\sub$$\tau$/=140 with wall deformations of │η$\sub$m/$\^$+/ 5. The approximate transformations provide flow structures as wall as turbulence statistics in good agreement with those from a complete coordinate transformation [Phys. Fluids 12, 3301 (2000)] and allow 25-30% savings in the CPU time as compared to the complete one.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제12권5호
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• pp.2273-2286
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• 2018

This paper describes transformations between elemental image arrays and a RGBD image for three-dimensional integral imaging and transmitting systems. Two transformations are introduced and analyzed in the proposed method. Normally, a RGBD image is utilized in efficient 3D data transmission although 3D imaging and display is restricted. Thus, a pixel-to-pixel mapping is required to obtain an elemental image array from a RGBD image. However, transformations and their analysis have little attention in computational integral imaging and transmission. Thus, in this paper, we introduce two different mapping methods that are called as the forward and backward mapping methods. Also, two mappings are analyzed and compared in terms of complexity and visual quality. In addition, a special condition, named as the hole-free condition in this paper, is proposed to understand the methods analytically. To verify our analysis, we carry out experiments for test images and the results indicate that the proposed methods and their analysis work in terms of the computational cost and visual quality.

• Communications for Statistical Applications and Methods
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• 제26권5호
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• pp.463-471
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• 2019

The variable transformations are useful ways to guarantee the functional relationships in the model. However, the presence of outliers may undermine the accuracy of transformation. This paper deals with response transformations in the partial linear models under the existence of outliers. A new procedure for response transformation and outliers detection is proposed. The procedure uses a sequential method for identifying outliers and dynamic graphical methods for an appropriate transformation. The graphical tools make it possible to catch diagnostic information by monitoring the movement of points in the data. The procedure is illustrated with several examples. Examples show that visual clues regarding the optimal transformation, the fittness of the model and the outlyness of the observations can be checked from the series of plots.

• 호남수학학술지
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• 제7권1호
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• pp.129-133
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• 1985

The object of this note is to discuss the relationship between some matrix transformations that naturally occur involving prime numbers in the theory of Summability.

• East Asian mathematical journal
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• 제19권1호
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• pp.113-120
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• 2003

We study how the second homotopy modules of group presentations are transformed by Tietze transformations and discuss some application.