• Journal of Advanced Navigation Technology
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• v.20 no.3
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• pp.203-209
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• 2016

Among the various fields in the communications, navigation, and surveillance/air traffic management (CNS/ATM) scheme, the surveillance field, which includes an automatic dependent surveillance - broadcast (ADS-B) system and a multilateration (MLAT) system, is implemented using satellite and digital communications technology. These systems provide better performance than radar, but still incur position error. To reduce the error, we propose an efficient information fusion method called the reweighted convex combination method for ADS-B and MLAT systems. The reweighted convex combination method improves aircraft tracking performance compared to the original convex combination method by readjusting the weights given to these systems. In this paper, we prove that the reweighted convex combination method always provides better performance than the original convex combination method. Performance from the fusion of ADS-B and MLAT improves an average of 51.51% when compared to the original data.

• Journal of Korea Water Resources Association
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• v.42 no.3
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• pp.201-212
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• 2009

The Tank model and the PRMS(Precipitation Runoff Modeling-modular System) model have been adopted to simulate runoff data from 1981 to 2001 year in the Seomgin-dam basin. However, the simulated runoff by each single model showed some deviations compared with the observed runoff, respectively. In this study a genetic algorithm combination runoff model has been proposed to minimize deviations between simulated runoff and observed runoff that should yield from single model such as Tank model or PRMS model. The proposed combination runoff model combining the simulated respective output of the Tank model and the PRMS model is to produce the optimum combination ratio of each single model applying to the genetic algorithm which may yield the minimum deviations between simulated runoff and observed one. The proposed combination runoff model has been applied to the Seomgin-dam basin. It has also been shown that the combination model by introducing optimal combination ratio should yield less deviations than single model such as the Tank model or the PRMS model.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2016.10a
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• pp.26-27
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• 2016

This study analyzes the engineering characteristics of mortar according to admixture replacement ratios in cement mortar in a high-intensity ternary system, and changes in FA and BS combination ratios, in order to deduce the optimal combination ratio of FA and BS. Results showed that due to the characteristics of unhardened mortar, flow rate increased with the increase in admixture replacement and FA combination ratios, whereas air quantity decreased and setting time was delayed. Due to the characteristics of light mortar, compression strength decreased at early material ages as the overall combination ratio of FA increased. The FA : BS combination ratio was 2 : 3 on day 28 of material age, proving the best and potentially optimal combination ratio.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.1
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• pp.133-139
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• 2013

Convex combination of two adaptive filters is an efficient method to improve adaptive filter performances. In this paper, a subband convex combination method of two adaptive filters for fast convergence rate in the transient state and low steady state error is presented. The cost function of mixing parameter for a subband convex combination is defined, and from this, the coefficient update equation is derived. Steady state analysis is used to prove the stability of the subband convex combination. Some simulation examples in system identification scenario show the validity of the subband convex combination schemes.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2001.11a
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• pp.65-68
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• 2001

Color is an imfortant factor for interior design. But both selecting the appropriate color and combinating many color are not easy. Actually designers spend much time searching interior images published in magazine to refer to previous cases of the color combination. And the side up, they undergo a process to try to search own hoping color in the interior design example of the magazine. As an alternative to avoid this inefficient process, this study provides a method to show good cases of color combination. This method can reduce trial and error in the determination the color combination.

• Korean Journal of Optics and Photonics
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• v.13 no.4
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• pp.275-282
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• 2002

We derived analytic formulae for the correction of spherical aberration, coma, and axial color of a two-components lens system consisted of a cemented doublet and a singlet by using the thin lens approximation. The correction formulae were applied to design a telephoto lens system. We examined two kinds of glass combinations in the design, one was crown-flint-crown combination and the other was flint-crown-flint combination. We found two kinds of achromatic aplanat solutions in the crown-flint-crown combination. For the case of flint-crown-flint combination, there were also two kinds of solutions, but their configurations are not useful in practice.

• Journal of the Korean Society for Precision Engineering
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• v.21 no.2
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• pp.52-59
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• 2004

In this paper, the automatic system generation algorithm based on the element combination algorithm discussed in the first part of this paper for designing an arbitrary type of the automatic transmissions is proposed. The powertrain design software using these algorithms is developed. This automotive powertrain design software with user-friendly graphic user interface has two main modules. The first module, the automatic power flow generation module, is already discussed in the previous paper. The second module dealing with the automatic system generation algorithm is discussed in this paper. The power-flow simulation software fur the arbitrary type of powertrain is then developed. The simulation and experimental results of the vehicle equipped with two planetary gear type automatic transmission are compared to validate the proposed algorithms and developed software. The simulation results demonstrate the good agreement with the experimental results.

• Proceedings of the KWS Conference
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• 1999.10a
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• pp.47-50
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• 1999

The term adaptive control is often used to describe recent advances in welding process control but strictly this only applies to system which are able to cope with dynamic changes in system performance. In welding applications, the term adaptive control may not imply the conventional control theory definition but may be used in the more descriptive sense to explain the need for the process to adapt to the changing welding conditions. This paper proposed a methodology for obtaining a good bead appearance based on multi-torches welding system with the vision system in SAW. The methodologies for adaptive filling control used the welding current/voltage, arc voltage/welding current/wire feed speed combination and welding speed by using the vision sensor. It was shown that the algorithm for the welding current/voltage combination and welding speed revealed the sound weld bead appearance compared with that of the voltage/current combination.

• Textile Coloration and Finishing
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• v.21 no.5
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• pp.27-34
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• 2009

PET fabric was dyed in black shade with disperse dyes of three primary color. The effect of combination ratio of dye concentration and energy type of disperse dye on dyeing and color property of black dyed PET fabric was investigated. Dyeing compatibility of disperse dyes of three primary color on PET was evaluated by comparison of dyeing rates of them. From the results, color property was dependent upon the combination ratio of dye concentration. In order to obtain low lightness ($L^*$) and black color, blue dye should be added enough. S-type disperse dye and $130^{\circ}C$ dyeing was suitable rather than SE-type dyes or $120^{\circ}C$ dyeing. Disperse dyes of three primary color used showed good dyeing compatibility at high dye concentration. Washfastness was fair to moderate and lightfastness was moderate.

• Journal of Practical Engineering Education
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• v.14 no.1
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• pp.179-194
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• 2022

After the work-study combination PBL method was first introduced into the P-Tech type in 2018, it was introduced into the degree-linked high-skilled professional course in operation as a pilot project in 2020, and ever since each department has reorganized the standard completion system to meet the PBL operation regulations and developed and operated PBL-based learning and training courses accordingly. With the expansion of the work-study combination PBL in 2021, the operating regulations were revised more elaborately. This paper examined the characteristics of the work-study combination PBL, the PBL operation regulations for each degree-linked high-skilled professional course, and the most recently implemented PBL operation regulations in detail through literature research. Based on this research, it introduced the development process and the result of the PBL-based standard completion system by the IT Convergence SW Engineering Department of KOREATECH and the result of the survey conducted to verify the suitability of the standard completion system after an operation and presented the challenges and improvements required for the degree-linked high-skilled professional course in relation to the changing operation regulations for the work-study combination PBL. This study is expected to provide universities with a reference to the development of training courses to smoothly apply the work-study combination PBL. It is also expected to contribute to the establishment and steady expansion of a unique PBL system that reflects the characteristics of work-study combination by presenting discourses on how the work-study combination PBL should develop, including high-skilled professional courses.