• 대한핵의학회:학술대회논문집
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• 2001.05a
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• pp.51-55
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• 2001

Regional MBF and MRGlc can be accurately estimated with N-13 ammonia and FDG PET using tracer kinetic methods including compartmental and non-compartmental approaches. Compartment modeling approaches are physiologically well characterized, but are methodologically more complicated. Noncompartmental analysis are easier to implement while the limitations and assumptions of the methods should be understood prior to the application of the method.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.6 no.1
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• pp.67-80
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• 2002

We formulate a pair of nondifferentiable symmetric dual variational problems with a square root term. Under invexity assumptions, we establish weak, strong, converse and self duality theorems for our variational problems by using the generalized Schwarz inequality. Also, we give the static case of our nondifferentiable symmetric duality results.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.4 no.1
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• pp.79-92
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• 2000

We investigate numerical properties of Newton's algorithm for improving an eigenpair of a real matrix A using only fixed precision arithmetic. We show that under natural assumptions it produces an eigenpair of a componentwise small relative perturbation of the data matrix A.

• Communications of the Korean Mathematical Society
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• v.19 no.1
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• pp.179-196
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• 2004

Mond-Weir type duals for multiobjective variational problems are formulated. Under generalized vector variational type I invexity assumptions on the functions involved, sufficient optimality conditions, weak and strong duality theorems are proved efficient and properly efficient solutions of the primal and dual problems.

• Journal of the Korean Mathematical Society
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• v.49 no.5
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• pp.927-945
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• 2012

An approximation of singular source terms in elliptic problems is developed and analyzed. Under certain assumptions on the curve where the singular source is defined, the second order convergence in the maximum norm can be proved. Numerical results present its better performance compared to previously developed regularization techniques.

• Bulletin of the Korean Mathematical Society
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• v.54 no.2
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• pp.647-654
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• 2017

Duality methods based on modified Lagrangian functional for solving a model crack problem is considered. Without additional assumptions of regularity of the solution of an initial problem duality ratio is established for initial and dual problem.

• Kyungpook Mathematical Journal
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• v.55 no.4
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• pp.1089-1095
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• 2015

In this paper, we study the existence and uniqueness of fixed points for generalized weak contractions under some proper assumptions. Our theorems include the known results of [1]-[6].

• Journal of the Korean Data and Information Science Society
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• v.14 no.3
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• pp.615-622
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• 2003

The severe acute respiratory syndrome(SARS) is a novel infectious disease with global impact. The rapid worldwide spread of SARS has led to 30 countries reporting cases of July 13, 2003. In this paper, we develop a statistical model for SARS-caused-death data under some assumptions. The model developed is a continuous time Markov process with a constant intensity for each stage.

• 제어로봇시스템학회:학술대회논문집
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• 1988.10a
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• pp.264-267
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• 1988

One of the major reasons of Adaptive Control is to control time varying systems. In this paper new adaptive algorithms are suggested for a class of linear time varying systems that satisfy certain assumptions. These algorithms consist of three modules, modeling, parameter estimation and control. The key feature of this paper is that power series of time varying parameters are used for estimation.

• Journal of applied mathematics & informatics
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• v.5 no.2
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• pp.475-488
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• 1998

Wolfe and Mond-Weir type duals for multiobjective con-trol problems are formulated. Under pseudo-invexity/quasi-invexity assumptions of the functions involved, weak and strong duality the-orems are proved to relate efficient solutions of the primal and dual problems.