• Bulletin of the Korean Chemical Society
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• v.34 no.7
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• pp.2125-2130
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• 2013

A new nickel(II) complex $[NiL^1]^{2+}$ ($L^1$ = 1-(2-aminoethyl)-3-(N-{2-aminoethyl}aminomethyl-1,3-diazacyclohexane) containing one 1,3-diazacyclohexane ring has been prepared selectively by the metal-template condensation of formaldehyde with N-(2-aminoethyl)-1,3-propanediamine and ethylenediamine at room temperature. The complex reacts with nitroethane and formaldehyde to yield the pentaaza macrocyclic complex $[NiL^2]^{2+}$ ($L^2$ = 8-methyl-8-nitro-1,3,6,10,13-pentaazabicyclo[13.3.1]heptadecane) bearing one C-$NO_2$ pendant arm. The reduction of $[NiL^2]^{2+}$ by using Zn/HCl produces $[NiL^3(H_2O)]^{2+}$ ($L^3$ = 8-amino-8-methyl-1,3,6,10,13-pentaazabicyclo[13.3.1]heptadecane) bearing one coordinated C-$NH_2$ pendant arm that is readily protonated in acid solutions. The hexaaza macrocyclic complex $[NiL^4]^{2+}$ ($L^4$ = 8-phenylmethyl-8-nitro-1,3,6,8,10,13-hexaazabicyclo[13.3.1]heptadecane) bearing one N-$CH_2C_6H_5$ pendant arm has also been prepared by the reaction of $[NiL^1]^{2+}$ with benzylamine and formaldehyde. The nickel(II) complexes of $L^1$, $L^2$, and $L^4$ have square-planar coordination geometry in the solid states and in nitromethane. However, they exist as equilibrium mixtures of the square-planar $[NiL]^{2+}$ (L = $L^1$, $L^2$, or $L^4$) and octahedral $[NiL(S)_2]^{2+}$ species in various coordinating solvents (S); the proportion of the octahedral species $[NiL(S)_2]^{2+}$ is strongly influenced by the ligand structure and the nature of the solvent. Synthesis, spectra, and chemical properties of the nickel(II) complexes of $L^1-L^4$ are described.

• Nuclear Engineering and Technology
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• v.14 no.1
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• pp.22-40
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• 1982

The nuclear LS-energy matrix elements have been calculated with the harmonic oscillator shell model wave functions for the configurations ( $l_{i}$ $l_{i+1}$｜ $l_{i}$ $l_{i+1}$) where 1$_1$= $l_{s}$ , $l_2$=lp, $l_3$=ld, 2s, $l_4$=1f, 2p, $l_{5}$ =1g, 2d, 3s. The resulting matrix elements are expressed in terms of both Talmi integrals $I_1$ and Slater integrals $F^{k}$ . In addition to this various sum rules are derived and applied to check the results of the calculations.ons.

• English Language & Literature Teaching
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• v.11 no.3
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• pp.39-56
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• 2005

This study is a small-scale replication study of Kubota (1998). Kubota discovered that L1 rhetoric was not the main cause of L2 writing problems. The conclusion of Kubota's study was in contrast to that of contrastive rhetoric research that claimed that the use of L1 rhetorical styles in L2 writing negatively affects the quality of L2 writing, in particular, at the organizational level. According to Kubota(1998), the use of Japanese rhetorical styles did not deteriorate the quality of English writing. By investigating Korean ESL learners, this replication study examined whether L1 and L2 writings have the same rhetorical styles and how L1 rhetorical styles affect the L2 writing quality. The study analyzed Korean and English persuasive writings written by 12 Korean ESL learners in terms of organization. The results show that Korean learners of English used different rhetorical styles in their L1 Korean writing and L2 English writing. However, there was a positive relationship between L1 Korean and L2 English organization scores.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.3 no.2
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• pp.123-130
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• 1991

The mixed convection heat transfer from vertical inline plates has been studied numerically by the finite difference method and experimentally with Mach-Zehnder interferometer. The dimensionless spacing, $s/L_1$, the relative length, $L_2/L_1$ and the dimensionless temperature ratio, ${\Phi}_2/{\Phi}_1$ are varied parametically. The lower plate mean Nusselt numbers show same values as $s/L_1$, ${\Phi}_2/{\Phi}_1$ and $L_2/L_1$ increase. The upper plate mean Nusselt numbers increase as $s/L_1$ and ${\Phi}_2/{\Phi}_1$ increase, but $L_2/L_1$ decreases. The upper plate mean Nusselt number is higher than the lower plate mean Nusselt for $s/L_1$ 1.8 at Re=100, $Gr=10^4$, Pr=0.71, $L_2/L_1=0.5$ and ${\Phi}_2/{\Phi}_1=1.0$. A comparison between the experimental and numerical results show good agreement.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.7
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• pp.3194-3216
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• 2018

Slow Feature Discriminant Analysis (SFDA) is a supervised feature extraction method inspired by biological mechanism. In this paper, a novel method called Two Dimensional Slow Feature Discriminant Analysis via $L_{2,1}$ norm minimization ($2DSFDA-L_{2,1}$) is proposed. $2DSFDA-L_{2,1}$ integrates $L_{2,1}$ norm regularization and 2D statically uncorrelated constraint to extract discriminant feature. First, $L_{2,1}$ norm regularization can promote the projection matrix row-sparsity, which makes the feature selection and subspace learning simultaneously. Second, uncorrelated features of minimum redundancy are effective for classification. We define 2D statistically uncorrelated model that each row (or column) are independent. Third, we provide a feasible solution by transforming the proposed $L_{2,1}$ nonlinear model into a linear regression type. Additionally, $2DSFDA-L_{2,1}$ is extended to a bilateral projection version called $BSFDA-L_{2,1}$. The advantage of $BSFDA-L_{2,1}$ is that an image can be represented with much less coefficients. Experimental results on three face databases demonstrate that the proposed $2DSFDA-L_{2,1}/BSFDA-L_{2,1}$ can obtain competitive performance.

• Journal of the Korean Society for Heat Treatment
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• v.21 no.1
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• pp.20-25
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• 2008

Structural studies have been performed on precipitation hardening and microstructural variations found in Ti-Al-Cr ternary $L1_0$- and $L1_2$-phase alloys using transmission electron microscopy. Both the $L1_0$ and $L1_2$ phase alloys harden by aging at 973 K after solution annealing at higher temperatures. The amount of age hardening of the $L1_2$ phase alloy is larger than that of the $L1_0$ phase alloy. The phase separation between $L1_0$ and $L1_2$ phase have not been observed by aging at 973 K. But $Al_2Ti$ was formed in each matrix alloy during aging. The crystal structure of the $Al_2Ti$ phase is a $Ga_2Zr$ type in the $L1_0$ and a $Ga_2Hf$ type in the $L1_2$ phase, respectively. At the beginning of aging the fine coherent cuboidal $Al_2Ti$-phase are formed in the $L1_0$ phase. By further aging, two variants of $Al_2Ti$ precipitates grow along the two {110} habit planes. On the other hand, in the $L1_2$ phase, the $Al_2Ti$ phase forms on the {100} planes of the $L1_2$ matrix lattice. After prolonged aging the precipitates are rearranged along a preferential direction of the matrix lattice and form a domain consisting of only one variant. It is suggested that the precipitation of $Al_2Ti$ in each matrix alloy occurs to form a morphology which efficiently relaxes the elastic strain between precipitate and matrix lattices.

• Bulletin of the Korean Chemical Society
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• v.11 no.3
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• pp.206-208
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• 1990

Cu(II) hexaazamacrotricyclic complexes $[Cu(L)](ClO_4)_2$ and $[(Cu(L)Cl]ClO_4$, where L = 1,3,6,9,11,14-hexaazatricyclo$[12.2.1.1^{6,9}]octadecane(L_1)$ or 1,3,6,10,12,15-hexaazatricyclo$[13.3.1.1^{6,10}]eicosane(L_2)$, have been prepared by the simple template condensation reactions of triamines, diethylenetriamine for $L_1$, and N-(2-aminoethyl)-1,3-propanediamine for $L_2$, with formaldehyde in the presence of $Cu(OAc)_2\;or\;CuCl_2$. The Cu(II) complexes of $L_1$ contain two 1,3-diazacyclopentane ring moieties and those of $L_2$ contain two 1,3-diazacyclohexane ring moieties that are fused to the 14-membered macrocyclic framework. Spectra indicate that complexes $[Cu(L)](ClO_4)_2\;and\;[Cu(L)Cl]ClO_4$ have square-planar and square-pyramidal chromophores, respectively. square-planar $[Cu(L)](ClO_4)_2$ are remarkably stable against ligand dissociation in acidic aqueous solutions. Square-pyramidal $[Cu(L)Cl]ClO_4$ complexes dissociate their axial Cl-ligands easily in aqueous solutions to form $[Cu(L)H_2O]^{2+}$ species. Infrared and UV/vis absorption spectra of the Cu(II) complexes reveal that Cu-N interactions and the ligand field strengths are significantly weaker in the complexes of $L_2$ than in the complexes of $L_1$.

• Honam Mathematical Journal
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• v.44 no.1
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• pp.135-145
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• 2022

This paper aims to investigate characterizations on parameters k₁, k₂, k₃, k₄, k₅, l₁, l₂, l₃, and l₄ to find relation between the class of 𝓗(k, l, m, n, o) hypergeometric functions defined by $$5_F_4\[{\array{k_1,\;k_2,\;k_3,\;k_4,\;k_5\\l_1,\;l_2,\;l_3,\;l_4}}\;:\;z\]=\sum\limits_{n=2}^{\infty}\frac{(k_1)_n(k_2)_n(k_3)_n(k_4)_n(k_5)_n}{(l_1)_n(l_2)_n(l_3)_n(l_4)_n(1)_n}z^n$$. We need to find k, l, m and n that lead to the necessary and sufficient condition for the function zF([W]), G = z(2 - F([W])) and $H_1[W]=z^2{\frac{d}{dz}}(ln(z)-h(z))$ to be in 𝓢^*(2^-r), r is a positive integer in the open unit disc 𝒟 = {z : |z| < 1, z ∈ ℂ} with $$h(z)=\sum\limits_{n=0}^{\infty}\frac{(k)_n(l)_n(m)_n(n)_n(1+\frac{k}{2})_n}{(\frac{k}{2})_n(1+k-l)_n(1+k-m)_n(1+k-n)_nn(1)_n}z^n$$ and $$[W]=\[{\array{k,\;1+{\frac{k}{2}},\;l,\;m,\;n\\{\frac{k}{2}},\;1+k-l,\;1+k-m,\;1+k-n}}\;:\;z\]$$.

• Korean Journal of Crystallography
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• v.18 no.1_2
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• pp.21-25
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• 2007

When a $CH_2Cl_2$ solution of the dipyridyl species L' (N,N'-bis-(1-pyridin-4-yl-ethylidene)-naphthalene-1,5-diamine) was layered onto the top of a MeOH solution of $Co(NO_3)_2{\cdot}6H_2O$, a molecular cobalt compound [$CoL_2(MeOH)(NO_3)_2$] (1), not a coordination polymer, was formed. X-ray structural analysis of compound 1 revealed that it contains the pyridyl-amine ligand L (N1-(4-imino-1-methyl-but-2-enylidene)-naphthalene-1,5-diamine), instead of L'. Structure of compound 1 strongly suggests that the original ligand L' has been hydrolyzed to ligand L during the reaction.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.25 no.6
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• pp.628-636
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• 2014

This paper describes the design and analysis of five-element planar array antenna of an anti-jamming satellite navigation system. We propose a design of multi-layer patch antenna for Global Positioning System(GPS) $L_1/L_2$ dual bands. The proposed antenna has two ports feeding network with a hybrid chip coupler for a broad bandwidth with Right-Handed Circular Polarization(RHCP). The measurement results show the bore-sight gains of 1.10 dBic($L_1$) and 0.37 dBic($L_2$) for the center element. The bore-sight gains of an edge element are 0.99 dBic($L_1$) and -0.57 dBic($L_2$). At a fixed elevation angle of $30^{\circ}$, antennas show average gains of -2.08 dBic ($L_1$) and -5.33 dBic($L_2$) for the center element, and average gains of -0.40 dBic($L_1$) and -2.09 dBic($L_2$) for the edge elements. The results demonstrate that the proposed array antenna is suitable for anti-jamming applications.