박종일 교수

Inverse synthetic aperture radar (ISAR) images represent the two-dimensional (2-D) spatial distribution of the radar crosssection (RCS) of an object and, thus, they can be applied to the problem of target identification. The traditional approach to ISAR imaging is the range-Doppler algorithm based on the 2-D Fourier transform. However, the 2-D Fourier transform often results in poor resolution ISAR images, especially when the measured frequency bandwidth and angular region are limited. Instead o

In this study, we propose a modified polar mapping classifier (M-PMC) with an efficient preprocessing scheme to classify synthetic aperture radar (SAR) targets from the public release database for moving and stationary target acquisition and recognition. M-PMC is evaluated under various SAR extended operating conditions (EOCs), which are designed to reflect real-world battlefield scenarios. Experimental outcomes from various EOCs show that M-PMC has good generalization capabilities and outperfor

One of the main problems in Seiberg-Witten theory is to find (SW)-basic classes and their invariants for a given smooth 4-manifold. The rational blow-down procedure introduced by Fintushel and Stern is one way to compute these invariants for some smooth 4-manifolds. In this paper, we extend their results to the general case. That is, we find (SW)-basic classes and Seiberg-Witten invariants for generalised rational blow-down 4-manifolds by using index computations.

To estimate camera pose, existing augmented reality (AR) techniques usually require fiducial markers with known geometry. However, placing a marker in the workspace of the user can be very visually intrusive. To overcome this limitation, a nonintrusive AR method using invisible markers that are created/drawn with an infrared (IR) ink is proposed and an IR marker tracking system is presented. This system includes additional algorithms to maintain reliable performance in a cluttered background. Th

This paper presents a method for evaluating the harmonic contributions of multiple harmonic sources to voltage distortion at the point of common coupling (PCC). The proposed method quantitatively represents harmonic contributions based on the equivalent voltage models of harmonic sources. The equivalent voltage models can be estimated using the recursive least square (RLS) algorithm and measured voltage and current at the PCC. The assessment of harmonic contribution heavily depends on the accura

In this article, for each finitely presented group <inline-formula content-type="math/mathml"> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="upper G"> <mml:semantics> <mml:mi>G</mml:mi> <mml:annotation encoding="application/x-tex">G</mml:annotation> </mml:semantics> </mml:math> </inline-formula> , we construct a family of minimal symplectic <inline-formula content-type="math/mathml"> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="4"> <mml:semantics> <mml:mn

Simply connected closed symplectic 4-manifolds with b 2 + = 1 and K2 = 0 are investigated. As a result, it is confirmed that most of homotopy elliptic surfaces {E(1)k|K is a fibred knot in S3} constructed by R. Fintushel and R. Stern in Invent. Math. 134 (1998) 363–400 are simply connected closed minimal symplectic 4-manifolds that do not admit a complex structure. 2000 Mathematics Subject Classification 57R17, 57R57 (primary), 14J26 (secondary).

In the construction of successful fuzzy models for nonlinear systems, the identification of an optimal fuzzy model system is an important and difficult problem. Traditionally, sGA(simple genetic algorithm) has been used to identify structures and parameters of fuzzy model because it has the ability to search the optimal solution somewhat globally. But SGA optimization process may be the reason of the premature local convergence when the appearance of the superior individual at the population evo

This paper deals with a method of quantifying the harmonic contribution of each harmonic source to system voltage distortion. Assessing the harmonic contribution of individual harmonic sources is essential for mitigating and managing system harmonic levels. Harmonic contributions can be evaluated using the principle of voltage superposition with equivalent voltage models for harmonic sources. In general, the parameters of equivalent voltage models are estimated numerically because it is difficul