• Journal of the Korean Mathematical Society
• /
• v.48 no.3
• /
• pp.513-527
• /
• 2011

The paper deals with the degenerate parabolic system with nonlinear boundary flux. By constructing the self-similar supersolution and subsolution, we obtain the critical global existence curve. The critical Fujita curve is conjectured with the aid of some new results.

• Bulletin of the Korean Mathematical Society
• /
• v.49 no.3
• /
• pp.655-667
• /
• 2012

In this paper, we deal with a critical point metric of the total scalar curvature on a compact manifold $M$. We prove that if the critical point metric has parallel Ricci tensor, then the manifold is isometric to a standard sphere. Moreover, we show that if an $n$-dimensional Riemannian manifold is a warped product, or has harmonic curvature with non-parallel Ricci tensor, then it cannot be a critical point metric.

• Proceedings of the Korean Information Science Society Conference
• /
• 2000.10a
• /
• pp.486-488
• /
• 2000

본 연구는 정형기법을 사용하여 Safety-Critical System의 개발 방법론을 제시한다. Safety-Critical System의 전체적인 개발 과정을 제시하고 Safety-Critical System 중의 하나인 원자력 발전소 시스템 중 Reactor Protection System(RPS)을 정형 명세(Formal Specification)하고 정형 검증(Formal Verification)하는 과정과 그에 따른 각 과정의 Compliance를 확인하는 예를 든다. 여기서 정형 명세에는 Software Cost Reduction(SCR)이하는 도구가 사용되었고, 정형 검증에는 SPIN이, Compliance를 확인하는 데에는 Prototype Verification System(PVS)를 사용하였다.

• The Transactions of the Korean Institute of Electrical Engineers A
• /
• v.54 no.11
• /
• pp.507-517
• /
• 2005

This paper presents the results of critical contingency analysis for the Korean power system which is performed to identify the impact of the critical contingencies on the Korean power system and set up a short term system operation planning for the purpose of preventing large scale blackout. The static and dynamic simulation is carried out for each critical contingency and the simulation results for each contingency are shown under the peak load condition for the year 2005, 2007 and 2010.

• Proceedings of the KSR Conference
• /
• 1998.11a
• /
• pp.313-320
• /
• 1998

The critical speed of a train running on the straight railway track is investigated by in-house program. The program is developed to find out nonlinear critical speed and it bases on the bifurcation theory. As a result, it is found that nonlinear critical speed exists on the lower speed band than linear critical speed and this fact imply a possibility of induction of a big accident.

• Nonlinear Functional Analysis and Applications
• /
• v.29 no.2
• /
• pp.419-434
• /
• 2024

This paper is devoted to the existence of solutions for Kirchhoff type equations with singular nonlinearities, sub-critical and critical exponent. By using the Nehari manifold and Maximum principle theorem, the existence of at least two distinct positive solutions is obtained.

• Bulletin of the Korean Mathematical Society
• /
• v.35 no.3
• /
• pp.421-431
• /
• 1998

We characterize real 4-dimensional Kahler metrices which are critical for natural quadratic Riemannian functionals defined on the space of all Riemannian metrics. In particular we show that such critical Kahler surfaces are either Einstein or have zero scalar curvature. We also make some discussion on criticality in the space of Kahler metrics.

• Journal of Dental Anesthesia and Pain Medicine
• /
• v.18 no.5
• /
• pp.315-317
• /
• 2018

• Journal of Dental Anesthesia and Pain Medicine
• /
• v.23 no.4
• /
• pp.241-243
• /
• 2023

• Korean Journal of Radiology
• /
• v.23 no.4
• /
• pp.488-490
• /
• 2022