• 제어로봇시스템학회:학술대회논문집
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• 1990.10b
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• pp.1071-1076
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• 1990

This paper proposes a navigation strategy of multiple autonomous mobile robots with communication within a specified space. Assuming that each robot has complete detectability with finite range, simple navigation strategy is derived by introducing repulsive forces between robots and attractive force between a robot and its goal point analogous to those between electric charges. When a robot is close to its goal point, a pseudo-domain based on the distance between the closest point of the domain boundary and the goal point is proposed to enhance its convergence to the goal state. This paper concludes with the results of computer simulation studies on the dynamic behavior of multiple interacting robots with the proposed navigation strategy.

• Journal of the Society of Naval Architects of Korea
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• v.45 no.1
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• pp.63-72
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• 2008

This study considers the motion response of multiple adjacent floating bodies in waves. As a method of solution, a three-dimensional Rankine panel method is adopted in time domain. For the validation of the developed numerical method, the motions of two adjacent Series 60 hulls and ship-barge model are estimated. The computational results are compared with other numerical and experimental analyses, showing favorable agreement.

• Convergence Security Journal
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• v.22 no.4
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• pp.169-178
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• 2022

In general, organizations operating multi-domain networks find it difficult to represent and manage multiple domain net works on a single screen space. Instead, most of them are managed with multiple screens visualizing network topology by domain or partitioning one screen area into multiple domains. We propose an efficient method to visualize the topology using only minimal connection information between domain-agnostic nodes in this work. This method visualizes the topology by utilizing centrality indices representing the influence of nodes in the network. Furthermore, the method dynamically segments the entire node's display area using virtual Root nodes to auto-separate domains and weights of child nodes and placing nodes in 3D space. Thus, although it is a straightforward method, the multi-domain network topology can be visualized with only minimal connection information between nodes.

• Journal of the Chungcheong Mathematical Society
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• v.30 no.4
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• pp.449-457
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• 2017

In this paper we study several generalizations of greatest common divisor of GCD domain with always the greatest common divisor.

• Wind and Structures
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• v.17 no.2
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• pp.227-244
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• 2013

Non-stationary extreme winds such as thunderstorm downbursts are responsible for many structural damages. This research presents a time domain approach for estimating along-wind load effects on tall buildings using multiple wind speed time history samples, which are simulated from evolutionary power spectra density (EPSD) functions of non-stationary wind fluctuations using the method developed by the authors' earlier research. The influence of transient wind loads on various responses including time-varying mean, root-mean-square value and peak factor is also studied. Furthermore, a simplified model is proposed to describe the non-stationary wind fluctuation as a uniformly modulated process with a modulation function following the time-varying mean. Finally, the probabilistic extreme response and peak factor are quantified based on the up-crossing theory of non-stationary process. As compared to the time domain response analysis using limited samples of wind record, usually one sample, the analysis using multiple samples presented in this study will provide more statistical information of responses. The time domain simulation also facilitates consideration of nonlinearities of structural and wind load characteristics over previous frequency domain analysis.

• Journal of Broadcast Engineering
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• v.26 no.1
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• pp.3-13
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• 2021

We propose a moire artifacts removal algorithm for screen-shot images using multiple domain learning. First, we estimate clean preliminary images by exploiting complementary information of the moire artifacts in pixel value and frequency domains. Next, we estimate a clean edge map of the input moire image by developing a clean edge predictor. Then, we refine the pixel and frequency domain outputs to further improve the quality of the results using the estimated edge map as the guide information. Finally, the proposed algorithm obtains the final result by merging the two refined results. Experimental results on a public dataset demonstrate that the proposed algorithm outperforms conventional algorithms in quantitative and qualitative comparison.

• Journal of electromagnetic engineering and science
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• v.18 no.1
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• pp.58-62
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• 2018

In this study, we propose a software-defined radio-based frequency interference emulator in the space-time domain. This emulator can easily model actual interference environments because of the versatile programming capability of the universal software radio peripheral and LabVIEW. As an example of an interfering network using the contention-based multiple access scheme in the time domain, we emulate a coordinated Wi-Fi network that consists of one access point and two Wi-Fi nodes. Results show that our emulator can successfully model multiple interfering signals in the Wi-Fi network and easily adjust various space-time domain parameters.

• 전기의세계
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• v.21 no.1
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• pp.13-16
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• 1972

Dynamic Programming is regarded as a very powerful tool for solving nonlinear optimization problem subject to a number of constraints of state and control variables, but has definite disadvantages that it requires much more computing time and consumes much more memory spaces than other technigues. In order to eliminate the above-mentioned demerits, this paper suggests a news technique called Multiple Dynamic Programming. The underlying principles are based on the concept of multiple passes that, instead of forming fin lattices in time-state plane as adopted in the conventional Dynamic Programming, the Multiple Dynamic Programming constitutes, at the first pass, coarse lattices in the feasible domain of time-state plane and determines the optimal state trajectory by the usual method of Dynamic Programming, and at the second pass again constitutes finer lattices in the narrower domain surrounded by both the upperand lower edges next to the lattice edges through which the first pass optimal trajectory passes and determines the more accurate optimal trajectory of state, and then at the third pass repeats the same processes, and so on. The suggested technique insures remarkable curtailment in amounts of computer memory spaces and conputing time, and its applicability has been demonstrated by a case study on the hydro-thermal power coordination in Korean power system.

• Journal of the Korean Institute of Telematics and Electronics T
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• v.36T no.1
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• pp.32-40
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• 1999

The analysis of logic function is performed by the spectral coefficients which transform the function domain data into the spectral domain data. By using the spectral techniques, analysis of MVL circuits is performaed, and the fault analysis and detecting methods of multiple-valued logic circuits are proposed in this paper.

• Proceedings of the IEEK Conference
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• 2002.07a
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• pp.281-284
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• 2002

Error resilience for image coding is an important component of multimedia communication system. Error resilience schemes address loss recovery from the compression perspective. Multiple description coding (MDC) is one of the error resilience techniques promising for robust video transmission. It is the way to achieve tradeoff description such as scalar quantization, correlating transform and the quantized frame expansion. In this paper, we consider Multiple Description Scalar Quantization (MDSQ) to wavelet domain. Conventional MDSQ schemes considered description with equal weights in each sub-bands. But, we can see that the each sub-bands is unequal contribution to whole image quality. Therefore, we experiment the multiple design MDSQ table to make probability of zero index high, which gives high efficiency in arithmetic symbol coder. We also compare our proposed method with the conventional methods and show improved performance in terms of redundancy-rate-distortion.