• Bulletin of the Korean Mathematical Society
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• v.54 no.1
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• pp.225-242
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• 2017

A family of $Ap{\acute{e}}ry$-like series involving reciprocals of central binomial coefficients is studied and it is shown that they represent transcendental numbers. The structure of such series is further examined in terms of finite combinations of logarithms and arctangents with arguments and coefficients belonging to a suitable algebraic extension of rationals. Monotonicity of certain quotients of weighted binomial sums which arise in the study of competitive cheap talk models is established with the help of a continuous extension of the discrete model at hand. The monotonic behavior of such quotients turns out to have important applications in game theory.

• Proceedings of the KSR Conference
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• 2005.05a
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• pp.597-603
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• 2005

The remediation of railroad contaminated soil is gaining wide attention, recently. In railroad field, modification of diesel supply field, equipment of roll pad, FRP panel, and iron pannel under diesel locomotive storages are used for the prevention of contamination expansions. However, cheap and efficient remediation technology has not been suggested yet. In this study, the contaminated ballast was remediated by blasting technology. Because the contaminants mainly resides on the surface of ballast, blasting these contaminants make it available to recycle the ballast. We carried out the remediation of oil-contaminated ballasts using the blasting technology, and we could remediate them nicely. This technology is expected to be used for the cheap and quick remediation of contaminated ballast.

• Transactions on Control, Automation and Systems Engineering
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• v.2 no.2
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• pp.140-148
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• 2000

This paper presents iterative schemes and continuation schemes for designing robust controllers which stabilize dynamic systems having bounded parametric uncertainties. Utilizing results of the cheap control problem, some existence conditions of the robust controller are obtained, which are different from the matching conditions. continuation schemes are used to overcome the divergence problem of iterative schemes. The roust controller design method is extended to nonlinear system ans easily implementable series solution is also obtained. Results are illustrated with simple examples.

• Archives of Plastic Surgery
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• v.46 no.1
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• pp.88-91
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• 2019

The burn center in our hospital is a national and regional (Southeast Asia) center. Of all admissions, 10% are related to blast explosions, and 8% due to chemical burns. In the acute burn management protocol of Singapore General Hospital, early surgical debridement is advocated for all acute partial-thickness burns. The aim of early surgical debridement is to remove all debris and unhealthy tissue, preventing wound infection and thereby expediting wound healing. In chemical burns, there can be stubborn eschars that are resistant to traditional debridement. We would like to present a novel technique using the diathermy scratch pad as a cheap and efficient tool for the dual purpose of surgical debridement and dermabrasion.

• Journal of Animal Environmental Science
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• v.10 no.3
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• pp.183-188
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• 2004

• 한국전기화학회:학술대회논문집
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• 2005.07a
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• pp.269-274
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• 2005

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1992.06a
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• pp.1-20
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• 1992

1. Ceramics as engineering Materials Ceramic \ulcorner :'material based on inorganic non-metallic compounds' Oxygen, Carbon, Nitrogen with metal (Al, Si) -cheap, plentiful and widespread element in the Earth -dirt: ceramic

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2007.06a
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• pp.393-394
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• 2007

• Bulletin of the Korean Chemical Society
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• v.29 no.12
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• pp.2346-2348
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• 2008

• Food Science of Animal Resources
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• v.41 no.1
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• pp.59-70
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• 2021

A method for simultaneous detection of fipronil (F) and its metabolites fipronil desulfinyl (FD), fipronil sulfide (FS), fipronil sulfone (FSO) in chicken eggs was applied and validated. It includes single-step, cheap, effective, rugged, safe-based method (SinChERS) for sample preparation and ultra high performance liquid chromatography coupled with mass spectrometry (UHPLC-MS/MS) for chemical analysis. Results suggested that formic acid enhanced the recovery of 4 target residues and 1% supplementation to acetonitrile gained higher recoveries than that of 5%. SinChERS integrated extraction and clean-up steps into one, with shorter time (1.5 h) to operate and higher recoveries (97%-100%) than HLB, Envi-Carb-NH2 and quik-easy-cheap-effective-rugged-safe method (QuEChERS), and it consumed the smallest volume of extracting solvent (10 mL) as QuEChERS. Quantitative analyses using external standard method suggested the linear ranges of 4 target compounds were 1-20 ㎍/L with R2 >0.9947. The limit of detection (S/N>3) and quantification (S/N>10) were 0.3 ㎍/kg and 1 ㎍/kg. Recoveries ranged from 89.0% to 104.4%, and the relative standard deviations (n=6) at 1, 10, and 20 ㎍/kg were lower than 6.03%. Thirty batches of domestic eggs (500 g each) were detected by the established SinChERS-based UHPLC-MS/MS and no target residues were detected in all samples. The method developed in this study is a rapid, sensitive, accurate and economic way for multi-residue analysis of fipronil and its metabolites in eggs.