• The Pure and Applied Mathematics
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• v.10 no.3
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• pp.145-161
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• 2003

Weak commutativity of a pair of maps was introduced by Sessa [On a weak commutativity condition of mappings in fixed point considerations. Publ. Inst. Math. (Beograd) (N.S.) 32(40) (1982),149-153] in fixed point considerations. Thereafter a number of generalizations of this notion has been obtained. The purpose of this paper is to present a brief development of weaker forms of commuting maps, and to obtain two fixed point theorems for noncommuting and noncontinuous maps on noncomplete metric spaces.

• Bulletin of the Korean Mathematical Society
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• v.46 no.2
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• pp.199-207
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• 2009

This note is a verification on the relations between almost linear and nearly additive maps; and the continuity of almost multiplicative nearly additive maps. Also we consider the stability of nearly additive and almost linear maps.

• Communications of the Korean Mathematical Society
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• v.9 no.4
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• pp.857-872
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• 1994

A PB-chain(Poincare-Birkhoff chain) is by definition a pair of elliptic and hyperbolic n-periodic orbits for a mapping and its existence has been well established numerically or analytically in many particular occasions such as in standard maps or twist maps [1, 8, 9] or Henon maps [1, 2, 12]. This paper gives focus on the investigaton of the appearance of such a PB-chain in a one-parameter family of general area-preserving maps and is in fact a generalization of the results given in [12] for a one-parameter family of specific area-preserving maps, so called Henon maps.

• Korean Journal of Geomatics
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• v.1 no.1
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• pp.51-59
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• 2001

The Government confirmed the action planning of digital mapping project for major thematic maps based on ‘Revised Plan for The Development of the National Geographic Information System’(NGIS). Mapping for major thematic maps was begun in 1998 when digital mapping project for topographic maps finished due to the delay of the action planning, and will selectively have produced the essential digital thematic maps according to the frequency of usage. The models of topographic-cadastral maps and administrative boundary maps around Suwon were produced in accordance with the presented draft. We presented specification for production of the most appropriate topographic-cadastral maps and administrative boundary maps through the analysis of the process of production, discussion and error check, and correction of the produced topographic-cadastral maps and administrative boundary maps. And we could make it easier to develop digital mapping project of topographic-cadastral maps and administrative boundary maps effectively by presenting the strategy for data input and maintenance, the cost model for carrying out the digital thematic map production, digital topographic maps, and the supplement of data model and data format. Topographic-cadastral maps has a wide range of usage but a lot of difficulties in the process of production and map update under use. So it seems that the study on users, university, private sector and municipal self-government must follow for promoting the use of topographic-cadastral maps.

• Honam Mathematical Journal
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• v.27 no.4
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• pp.641-647
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• 2005

This note is a verification on the relations between multiplicative and almost multiplicative linear maps; and the continuity of almost multiplicative linear maps.

• Korean System Dynamics Review
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• v.1 no.2
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• pp.91-111
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• 2000

Causal maps or cognitive maps have been widely used to get insights for complex systems or decision makers. When insights come from the system behavior rather than its structure, we need simulation of causal maps and cognitive maps. In this paper, a method for directly converting causal maps and cognitive maps into stock-flow diagrams that can be simulated in computers in proposed. This method is called as NUMBER. NUMBER is an abbreviation for 'Normal Unit Modeling By Elementary Relationship'. In this paper, NUMBER is applied to a cognitive map of policy maker to show its usefulness.

• Bulletin of the Korean Mathematical Society
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• v.56 no.5
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• pp.1327-1340
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• 2019

We establish a monotonicity formula of V-harmonic maps by using the stress-energy tensor. Use the monotonicity formula, we can derive a Liouville type theorem for V-harmonic maps. As applications, we also obtain monotonicity and constancy of Weyl harmonic maps from conformal manifolds to Riemannian manifolds and ${\pm}holomorphic$ maps between almost Hermitian manifolds. Finally, a constant boundary-value problem of V-harmonic maps is considered.

• Korean System Dynamics Review
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• v.8 no.1
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• pp.97-115
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• 2007

In System Dynamics, causal maps are used as a tool for analyzing dynamic problems and discussing the outcome of analyzed problems. However there are some limitations to use causal maps. In the drawing phase of causal maps, the high abstraction of variables that constitutes problems makes it difficult to find out correct information. And principles or rules to check errors on causal maps are not sufficient yet. Moreover, simulation modeling tasks are required to be concerned separately from drawing causal maps because causal maps cannot provide enough information to simulation modeling. In order to overcome these limitations, this study shows ways that ensure validity, increase power of expression of causal maps and improve the connection between causal maps and simulation modeling.

• Korean Journal of Geomatics
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• v.2 no.1
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• pp.83-89
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• 2002

The cadastral maps as many as about 750,000 map sheets to cover 34,751,000 parcels of land of Korea, are being digitalized. The problem of shrinkage-expansion of the paper cadastral maps has to be resolved for the new digital maps, where the nodes and vertices of the parcel boundaries are represented by coordinates. The photo coordinate refinement techniques, two dimensional projective transformation and local area transformation as in the reseau grid method, were introduced for this distortion correction. Using the fact that original maps drawn on the plane tables in field from 1910 to 1918 have grid lines and have been preserved well, a strategic flow to apply the refinement techniques to the digital maps with the original maps as controls was developed. To accommodate the presence or absence of the original maps and grid lines, and different scales and sizes of the maps, the strategy was implemented by a computer program package. Various distortions and corrections were simulated and errors were evaluated. The RMS errors in the corrected digital maps were allowable, thus, the method developed in this study was to be applicable for the digital cadastral maps.

• Journal of the Korean Mathematical Society
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• v.42 no.6
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• pp.1205-1213
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• 2005

Applying a fixed point theorem for compact admissible maps due to Gorniewicz, we prove that under certain conditions each count ably condensing admissible maps in Frechet spaces has a positive eigenvalue. This result has many consequences, including the well-known theorem of Krasnoselskii.