Changki Jeong

Reciprocally convex approach to stability of systems with time-varying delays

Whereas the upper bound lemma for matrix cross-product, introduced by Park (1999) and modified by Moon, Park, Kwon, and Lee (2001), plays a key role in guiding various delay-dependent criteria for delayed systems, the Jensen inequality has become an alternative as a way of reducing the number of decision variables. It directly relaxes the integral term of quadratic quantities into the quadratic term of the integral quantities, resulting in a linear combination of positive functions weighted by the inverses of convex parameters. This paper suggests the lower bound lemma for such a combination, which achieves performance behavior identical to approaches based on the integral inequality lemma but with much less decision variables, comparable to those based on the Jensen inequality lemma.

Improved approach to robust stability and H∞ performance analysis for systems with an interval time-varying delay

Abstract An improved delay- and range-dependent robust stability and H ∞ performance analysis criterion for systems with an interval time-varying delay is investigated. A novel Lyapunov–Krasovskii functional containing triple-integral terms is established, and an extended free-weighting matrix method, double-integral inequality method is subsequently proposed. Numerical examples validate the effectiveness of the proposed double-integral inequality method and show that our approach is less conservative than existing methods.

A defect inspection method for TFT panel using the compute unified device architecture (CUDA)

In this paper, a parallel algorithm to inspect defects of thin film transistor liquid crystal displays (TFT-LCD) panel is presented. The algorithm is implemented on a graphics processing unit (GPU) using the compute unified device architecture (CUDA) development environment. The result shows better performance compared to the one implemented on a CPU.

Implementation of TFT inspection system using the common unified device architecture (CUDA) on modern graphics hardware

Nowadays, computational power of graphics hardware is strong enough to be used in many applications requiring parallel computing. It can be used any other areas even unrelated to the graphics displays. Following these trends, we adapted this general purpose graphics processing unit (GPGPU) for thin film transistor liquid crystal displays (TFT-LCD) inspection. In this paper, we describe practical system components and the implementation including compute unified device architecture (CUDA) programming. An experimental result compares to the previous system which uses CPU as a main processor.

Establishment of field robot system for observation of power plant facilities

As power plant facilities are being deteriorated, their safety is getting more importance, and more routine surveillance is being required to preserve safety of the facilities. For this purpose, this paper presents a field robot system which performs the surveillance of power plant facilities instead of human workers from the viewpoint of the workerspsila safety and work efficiency.