• Journal of applied mathematics & informatics
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• 제18권1_2호
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• pp.25-43
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• 2005

Let F be a finite field of prime power order q(odd) and the multiplicative order of q modulo $2^{n}\;(n>1)\;be\; {\phi}(2^{n})/2$. If n > 3, then q is odd number(prime or prime power) of the form $8m{\pm}3$. If q = 8m - 3, then the ring $R_{2^n} = F[x]/ < x^{2^n}-1 >$ has 2n primitive idempotents. The explicit expressions for these primitive idempotents are obtained and the minimal QR cyclic codes of length $2^{n}$ generated by these idempotents are completely described. If q = 8m + 3 then the expressions for the 2n - 1 primitive idempotents of $R_{2^n}$ are obtained. The generating polynomials and the upper bounds of the minimum distance of minimal QR cyclic codes generated by these 2n-1 idempotents are also obtained. The case n = 2,3 is dealt separately.

• 한국전기전자재료학회논문지
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• 제18권6호
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• pp.582-586
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• 2005

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 and threading dislocation (TD) density decreased from $3.21\times10^9\;cm^{-2}\;to\;9.7\times10^8\;cm^{-2}$. 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 GaN layer.

• 충청수학회지
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• 제7권1호
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• pp.117-122
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• 1994

In this paper we show that if {$H_n$} is a continuous strong higher derivation of order n on an ultraprime Banach algebra with a constant c, then $c||H_1||^2{\leq}4||H_2||$ and for each $1{\leq}l$ < n $$c^2||H_1||\;||H_{n-l}{\leq}6||H_n||+\frac{3}{2}\sum_{\array{i+j+k=n\\i,j,k{\geq}1}}||H_i||\;||H_j||\;||H_k||+\frac{3}{2}\sum_{\array{i+k=n\\i{\neq}l,\;n-1}}||H_i||\;||H_k|| $$ and for a strong higher derivation {$H_n$} of order n on a prime ring A we also show that if [$H_n$(x),x]=0 for all $x{\in}A$ and for every $n{\geq}1$, then A is commutative or $H_n=0$ for every $n{\geq}1$.

• 대한화학회지
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• 제16권6호
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• pp.369-372
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• 1972

메탄올, N, N-dimethylformamide 및 acetonitrile속에서 이염기성 카르복시산 $(HOOC(CH_2)_nCOOH$, n=0∼4)의 해리상수를 유리전극을 사용하여 전위차법으로 측정했다. 두 용매간에서 각 산의 전해리상수의 차는 거의 일정한 값이 되며, 이 값은 일염기성 카르복시산의 해리상수의 차와 거의 일치했다. 그리고 $K_1/K_2$의 값은 양성자성용매인 물과 메탄올에서보다 반양성자성용매인 N,N-dimethylformamide와 acetonitrile에서 훨씬 더 크다.

• Kyungpook Mathematical Journal
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• 제56권3호
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• pp.1003-1016
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• 2016

In this paper, we introduce a new kind of slant helix for null curves called null $W_n$-slant helix and we give a definition of new harmonic curvature functions of a null curve in terms of $W_n$ in (n + 2)-dimensional Lorentzian space $M^{n+2}_1$ (for n > 3). Also, we obtain a characterization such as: "The curve ${\alpha}$ s a null $W_n$-slant helix ${\Leftrightarrow}H^{\prime}_n-k_1H_{n-1}-k_2H_{n-3}=0$" where $H_n,H_{n-1}$ and $H_{n-3}$ are harmonic curvature functions and $k_1,k_2$ are the Cartan curvature functions of the null curve ${\alpha}$.

• 대한한방체열의학회지
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• 제3권1호
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• pp.60-66
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• 2004

Purpose This study is to examine of Neurometer for the diagnosis of cold hypersensitivity Method Among patients who visited the oriental gynecological department in Kangnam Korean Hospital from October. 2000 to December. 2000, 37 women were diagnosed as cold hypersensitivity by D.I.T.I. We measured the limbs' temperature by D.I.T.I. and Current perception threshold(CPT) of median N., ulnar N., radial N., peroneal N., sural N., tibial N., saphenous N. by neurometer Patients were divided into mild and severe group depending on the temperature difference between proximalis and distalis in limbs Result and Conclusion 1. In severe group, CPT of median N., ulnar N., radial N. was higher on 250Hz and 200Hz. 2. In severe group, Mean CPT of peroneal N., sural N., tibial N., saphenous N. was higher on every Hz.

• Bulletin of the Korean Chemical Society
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• 제15권8호
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• pp.669-673
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• 1994

Coordination isomers of cis-(N-N)Pt(Glu) prepared by reaction of cis-(N-N)Pt($SO_4$) (N-N=2$NH_3$, ethylenediamine(en),(R,R)-1,2-diaminocyclohexane (DACH), N,N,N',N'-tetramethylethylenediamine (TMEDA)) with barium glutamate in water have been monitored and characterized by $^1H-NMR$, $^{13}C-NMR$, IR, and mass spectra. The reaction at room temperature affords the mixture of O,O'-and N, ${\alpha}$ O-chelated platinum(II) complexes. The O,O'-chelate initially formed isomerized to N,${\alpha}$O-chelate on standing for a long time or increasing temperature. The ratio of the two isomers at room temperature depends on the nature of the nitrogen donor coligand (N-N).

• Bulletin of the Korean Chemical Society
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• 제13권6호
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• pp.676-680
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• 1992

Irradiation of N-t-butyl-N-chloro-3-phenylpropanesulfonamide (1a) in benzene at $20^{\circ}C$ using 450 W high pressure mercury arc lamp in the presence of oxygen affored N-t-butyl-3-phenylpropanesulfonamide (2), N-t-butyl-3-chloro-3-phenylpropanesulfonamide (3), and N-t-butyl-3-oxo-3-phenylpropanesulfonamide (4). Similarly, N-t-butyl-4- (5), N-t-butyl-4-chloro-4- (6), and N-t-butyl-4-phenylbutanesulfonamides (7) were obtained from N-t-butyl-N-chloro-4-phenylbutanesulfonamide (1b). However, irradiation of N-t-butyl-N-chloro-5-phenylpentanesulfonamide (1c) under the same conditions gave complex mixtures. These results indicate that sulfonamidyl radical generated from each of 1a and 1b can abstract intramolecularly a hydrogen atom from the benzylic position only by forming six and seven-membered transition states, respectively.

• 대한수학회보
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• 제58권6호
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• pp.1507-1520
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• 2021

Let R be a commutative ring with 1 ≠ 0, n be a positive integer and M be an R-module. In this paper, we introduce the concept of weakly quasi n-absorbing submodule which is a proper generalization of quasi n-absorbing submodule. We define a proper submodule N of M to be a weakly quasi n-absorbing submodule if whenever a ∈ R and x ∈ M with 0 ≠ aⁿ x ∈ N, then aⁿ ∈ (N :_R M) or a^n-1 x ∈ N. We study the basic properties of this notion and establish several characterizations.

• 전자통신동향분석
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• 제38권1호
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• pp.36-45
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• 2023

The increasing demand for ultra-high efficiency of compact power conversion systems for electric vehicle applications has brought GaN power semiconductors to the fore due to their low conduction losses and fast switching speed. In particular, the development of materials and core device processes contributed to remarkable results regarding the publication of vertical GaN power devices with high breakdown voltage. This paper reviews recent advances on GaN material technology and vertical GaN power device technology. The GaN material technology covers the latest technological trends and GaN epitaxial growth technology, while the vertical GaN power device technology examines diodes, Trench FETs, JFETs, and FinFETs and reviews the vertical GaN PiN diode technology developed by ETRI.