• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.658-659
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• 2006

Magnetron sputtered TiN, (Ti, Al)N and TiN/(Ti, Al)N multilayer coatings grown on cemented carbide substrates have been characterized by using electron probe microanalysis (EPMA), X-ray diffraction (XRD), scanning electron spectroscopy (SEM), nanoindentation, scratcher and cutting tests. Results show that TiN coating is bell mouth columnar structures, (Ti, Al)N coating is straight columnar structures and the modulation structure has been formed in the TiN/(Ti, Al)N multilayer coating. TiN/(Ti, Al)N multilayer coating exhibited higher hardness, better adhesion with substrate and excellent cutting performance compared with TiN and (Ti, Al)N coating.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.1
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• pp.121-124
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• 2004

We have grown GaN layers with in-situ SiN mask by metal organic chemical vapor deposition(MOCVD) and study the physical properties of the GaN layer. We have also investigate the effect of the SiN mask on its optical property. By inserting a SiN mask, (102) the full width at half maximum(FWHM) decreased from 480 arcsec to 409 arcsec. The PL intensity of GaN with SiN mask improved 2 times to that without SiN mask. We have thus shown that the SiN mask improved significantly the physical and optical properties of the GgN layer.

• 한국수학교육학회지시리즈B:순수및응용수학
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• 제15권2호
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• pp.163-167
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• 2008

This paper presents characterizations of the Weibull distribution by the independence of record values. We prove that $X\;{\in}\;W\;EI ({\alpha})$, if and only if $\frac {X_{U(n+l)}} {X_{U(n+1)}\;+\;X_{U(n)}}$ and $X_{U(n+1)}$ for $n{\geq}1$ are independent or $\frac {X_{U(n)}} {X_{U(n+1)}\;+\;X_{U(n)}}$ and $X_{U(n+1)}$ for $n{\geq}1$ are independent. And also we establish that $X\;{\in}\;W\;EI({\alpha})$, if and only if $\frac {X_{U(n+1)}\;-\;X_{U(n)}} {X_{U(n+1)}\;+\;X_{U(n)}}$ and $X_{U(n+1)}$ for $n{\geq}1$ are independent.

• 한국식품영양학회지
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• 제12권4호
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• pp.415-420
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• 1999

Petal of Azalea(Rhododendron mucronulatum Turcz) was incubated with Gokja at 3$0^{\circ}C$ for seven days and the essential oil components of petal of Azalea before and after incubated were analyzed using a GC/MSD. Ten or more essential oil components including n-heneicosane n-tricosane n-tetreacosane n-pentacosane n-heptacosane n-nonacosane and n-hentriacontane were identified from the petal of Azal-ea before incubated while oxygen-containng compounds including (E)-heptenal 2-ethoxy-1 -hexanol n-hexadecanoic acid methyl ester 9, 12-octadecadienoic acid methyl ester 9,12,15-octadecatrienoic acid methyl ester, n-octadecanoic acid methyl ester n-eicosanoic acid methyl ester and 9-docosaenoic acid methyl ester as well as n-alkanes such as n-tricosane that n-pentacosane were identified from the petal of Azalea after incubated. These results suggest that n-alkanes in petal of Azalea might be degraded and some oxygen-containing compounds such as aldehyde, esters and /or acids might be produced when pet-al of Azalea is incubated with Gokja.

• Bulletin of the Korean Chemical Society
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• 제6권6호
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• pp.369-374
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• 1985

A new flexible quadridentate ligand, N,N'-dimethylethylenediamine-N,N'-di-${\alpha}$-propionic acid (dmedpa) has been synthesized, and diammine and ethylenediamine cobalt(III) complexes of dmedpa, $[Co(dmedpa)(NH_3)_2]^+$ and $[Co(dmedpa(en)]^+,$ have been prepared. Only s-cis isomer has been yielede. A known N,N'-dimethylethylediamine-N,N'-diacetic acid (dmedda) has also been prepared. Dichloro cobalt(III) complexes of both dmedda and dmedpa have been prepared. Only the s-cis isomer has been yielded in the $[Co(dmedda)Cl_2]^-$ complex, while only the uns-cis isomer has been obtained for the $[Co(dmedpa)Cl_2]^-$ complex.

• Bulletin of the Korean Chemical Society
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• 제4권4호
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• pp.171-175
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• 1983

This paper reports new phosphonamide derivatives which contain diethyl aminomethylphosphonate, diethyl DL-1-aminobenzylphosphonate and 6-aminopenicillanic acid; N-(ethyl phthalimidomethylphosphonyl)-L-methionine methyl ester, N-(ethyl phthalimidomethylphosphonyl)-L-valine ethyl ester, N-[ethyl N-(methoxycarbonylmethyl)benzylphosphonamido]-2-phthalimidoacetamide, N-[ethyl N-(diethyl phosphonylbenzyl)methylphthalamido] phthalimide, N-[ethyl {ethyl N-(diethyl phosphonylbenzyl)aminomethylphosphonamido} phosphonylmethyl] phthalimide, N-[ethyl N-(diethyl phosphonylbenzyl)methylphosphonamido]-2-phthalimidoacetamide, N, N'-bis (ethyl phthalimidomethylphosphonyl)ethylene diamine, 6-(ethyl DL-1-aminobenzylphosphonamido) penicillanic acid, ethyl N-(ethoxycarbonylmethyl)-1-aminobenzylphosphonamide, ethyl N-(diethyl phosphonylbenzyl)aminomethylphosphonamide and N,N'-bis (ethyl aminomethylphosphonyl) ethylene diamine.

• Journal of applied mathematics & informatics
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• 제40권3_4호
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• pp.709-717
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• 2022

The objective of this research is to prove that an additive mapping T : R → R is a left as well as right centralizer on R if it satisfies any one of the following identities: (i) T(xⁿyⁿ + yⁿxⁿ) = T(xⁿ)yⁿ + yⁿT(xⁿ) (ii) 2T(xⁿyⁿ) = T(xⁿ)yⁿ + yⁿT(xⁿ) for each x, y ∈ R, where n ≥ 1 is a fixed integer and R is any n!-torsion free semiprime ring. In addition, we talk over above identities in the setting of *-ring(ring with involution).

• 대한수학회논문집
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• 제38권4호
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• pp.1075-1090
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• 2023

In this paper, we study new classes of operators k-quasi (m, n)-paranormal operator, k-quasi (m, n)^*-paranormal operator, k-quasi (m, n)-class 𝒬 operator and k-quasi (m, n)-class 𝒬^* operator which are the generalization of (m, n)-paranormal and (m, n)^*-paranormal operators. We give matrix characterizations for k-quasi (m, n)-paranormal and k-quasi (m, n)^*-paranormal operators. Also we study some properties of k-quasi (m, n)-class 𝒬 operator and k-quasi (m, n)-class 𝒬^* operators. Moreover, these classes of composition operators on L² spaces are characterized.

• 한국진공학회지
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• 제10권2호
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• pp.189-193
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• 2001

TiN을 불소의 확산 방지막으로 사용한 W-TiN 복층 게이트 소자의 물리적.전기적 특성 변화를 살펴보았다. TiN 스퍼터링 증착시 $N_2$/Ar 가스 비율이 증가할수록 TiN 박막은 N-과다막이 되어 비저항이 증가하였으나, W-TiN복층 구조에서는 $N_2$/Ar가스 비율이 증가할수록 상부 텅스텐 박막의 결정화가 증가하여 비저항이 감소하였다. 한편, 같은 $N_2$/Ar 비율의 경우, TiN 박막 열처리 온도 변화(600~$800^{\circ}C$)에 무관하게 W(110) 방향으로 우선 배향된 결정 구조를 보였다. 누설 전류 특성은 TiN증착시 $N_2$/Ar 비율 변화에 무관하게 우수하였으며, TiN을 확산 방지막으로 사용함으로서 순수 텅스텐 전극만을 적용시 나타나는 초기 저전계 누설 특성을 향상시킬 수 있음을 확인하였다.

• 한국토양비료학회지
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• 제49권6호
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• pp.712-719
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• 2016

Understanding N mineralization dynamics in soil is essential for efficient nutrient management. An anaerobic incubation experiment was conducted to examine N mineralization potential and N mineralization rate of the organic amendments with different C:N ratio in paddy soil. Inorganic N in the soil sample was measured periodically under three temperature conditions ($20^{\circ}C$, $25^{\circ}C$, $30^{\circ}C$) for 90 days. N mineralization was accelerated as the temperature rises by approximately $10%^{\circ}C^{-1}$ in average. Negative correlation ($R^2=0.707$) was observed between soil inorganic N and C:N ratio, while total organic carbon extract ($R^2=0.947$) and microbial biomass C ($R^2=0.824$) in the soil were positively related to C:N ratio. Single exponential model was applied for quantitative evaluation of N mineralization process. Model parameter for N mineralization rate, k, increased in proportion to temperature. N mineralization potential, $N_p$, was very different depending on C:N ratio of organic input. $N_p$ value decreased as C:N ratio increased, ranged from $74.3mg\;kg^{-1}$ in a low C:N ratio (12.0 in hairy vetch) to $15.1mg\;kg^{-1}$ in a high C:N ratio (78.2 in rice straw). This result indicated that the amount of inorganic N available for crop uptake can be predicted by temperature and C:N ratio of organic amendment. Consequently, it is suggested that the amount of organic fertilizer application in paddy soil would be determined based on temperature observations and C:N ratio, which represent the decomposition characteristics of organic amendments.