• Bulletin of the Korean Chemical Society
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• 제27권8호
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• pp.1099-1114
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• 2006

Our studies in the area of single electron transfer (SET) photochemistry have led to the discovery of efficient processes, in which regioselective formation of carbon-centered radicals takes place by nucleophile assisted desilylation of $\alpha$-trialkylsilyl substituted ether, thioether, amine and amide centered cation radicals. The rates of bimolecular desilylation of the intermediate cation radicals exceed those of other cation radical $\alpha$-fragmentation processes (e.g.,-deprotonation). This sereves as the basis for the design of highly regioselective, SET-induced photomacrocyclization reactions of polyether, polythioether, polyamide, and polypeptide linked phthalimides. Photocyclization reactions of trimethylsilyl-terminated substrates in these families are unique in that they produce polyfunctionalized macrocyclic substances in a highly efficient and regioselective manner. In addition, our studies in this area have led to important information about the factors that govern chemical and quantum efficiencies that should be applicable to a wide variety of redox processes promoted by SET from substrates containing more than one electron donor site.

• Journal of applied mathematics & informatics
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• 제39권5_6호
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• pp.689-701
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• 2021

The purpose of this paper is to optimize the number of source places required for the unique representation of the destination using the tools of graph theory. A subset S of vertices of a graph G is called a rational resolving set of G if for each pair u, v ∈ V - S, there is a vertex s ∈ S such that d(u/s) ≠ d(v/s), where d(x/s) denotes the mean of the distances from the vertex s to all those y ∈ N[x]. A rational resolving set is called minimal rational resolving set if no proper subset of it is a rational resolving set. In this paper we study varieties of minimal rational resolving sets defined on the basis of its complements and compute the minimum and maximum cardinality of such sets, respectively called as lower and upper rational metric dimensions for power of a path P_n analysing various possibilities.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1999년도 하계종합학술대회 논문집
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• pp.333-336
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• 1999

In this paper, a new high speed parallel input and parallel output GF(2$^{m}$ ) multiplier based on standard basis is proposed. The concept of the multiplication in standard basis coordinates gives an easier VLSI implementation than that of the dual basis. This proposed algorithm and method of implementation of the GF(2$^{m}$ ) multiplication are represented by two kinds of basic cells (which are the generalized and fixed basic cell), and the minimum critical path with pipelined operation. In the case of the generalized basic cell, the proposed multiplier is composed of $m^2$ basic cells where each cell has 2 two input AND gates, 2 two input XOR gates, and 2 one bit latches Specifically, we show that the proposed multiplier has smaller complexity than those proposed in 〔5〕.

• 대한전기학회논문지:시스템및제어부문D
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• 제52권10호
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• pp.591-597
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• 2003

In this paper, a best-basis selection algorithm that improves the performance of the coding gains and the computational complexity is proposed. The proposed algorithm limits the computational complexity according to the resolved threshold value and decomposes the parent subbands by using the top-down tree search and the relative energy between the parent subbands and the child subbands. For the experiments of the proposed algorithm, the bit-rates, the peak signal-to-noise ratio (PSNR), and the reconstructed images are presented by using the Quad-tree coder. The result of the proposed algorithm is compared to that of DWT algorithm using the Quad-tree coder for a set of standard test images. In addition, the result of the proposed algorithm is compared to that of JPEG-2000 algorithm and that of S+P algorithm.

• 한국통신학회논문지
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• 제10권1호
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• pp.31-37
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• 1985

An interesting area of application which makes use of the unique features of the walsh series is that on non-linear stochastic problems. In particular, some success has been obtained in improving the efficiency of signal detection for those transducers which are essentially non-linear in operation. The set of harmonically-related nonorthogonal triangle waves is shown to form a basis apanning the same function space representable by fourier(trigonometric) series. A method for generating nonorthogonal bases for signal representation is presented tailor-made basis function can be used for specific purposes. Fundamental proofs of the basis properties of the representation are examined along with examples illustrating the techniques and computer simulation.

• Bulletin of the Korean Chemical Society
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• 제35권10호
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• pp.2911-2916
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• 2014

The gas phase structures, energetics, and interconversion pathways of five lowest energy conformers of acetylcholine were examined employing the B3LYP, MP2, and CCSD(T) methods in conjunction with diverse basis sets including the correlation consistent aug-cc-pVDZ and aug-cc-pVTZ basis sets. It is found that use of adequate basis set containing proper polarization and diffuse functions capable of describing the floppy potential energy surface of acetylcholine is important in correctly predicting the relative stability of these conformers. The interconversion pathways and barrier heights between these conformers were elucidated by examining the potential energy surface for torsional motion, which also manifested the presence of chiral conformations of acetylcholine corresponding to the original conformations. On the basis of high level electronic energy calculations and thermal contribution analysis, four lowest energy conformers appear to be populated in the energy range of less than 1 kcal/mol at room temperature.

• 대한수학회지
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• 제45권3호
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• pp.711-725
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• 2008

We give an explicit construction of Grobner-Shirshov pairs and monomial bases for finite-dimensional irreducible representations of the simple Lie algebra $sp_4$. We also identify the monomial basis consisting of the reduced monomials with a set of semistandard tableaux of a given shape, on which we give a colored oriented graph structure.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 G
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• pp.2203-2205
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• 1998

This paper describes fuzzy radial basis function networks(FRBFN) extracting fuzzy rules through the learning from training data set. The proposed FRBFN is derived from the functional equivalence between RBF networks and fuzzy inference systems. The FRBFN learn by assigning new fuzzy rules and updating the parameters of existing fuzzy rules. The parameters of the FRBFN are adjusted using the standard LMS algorithm. The performance of the FRBFN is illustrated with function approximation and system identification.

• Bulletin of the Korean Chemical Society
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• 제17권8호
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• pp.754-759
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• 1996

Ab initio Hartree-Fock and Becke 3-Lee-Yang-Parr (B3LYP) density functional theory calculations using 6-31G* basis set were carried out to study the vibrational spectra of anthracene neutral (h10 and d10) and radical cation (h10). We report results of the fundamental vibrational frequencies obtained on the basis of the calculations. The assignments of fundamentals show a one-to-one correspondence between the observed and calculated fundamentals.

• Bulletin of the Korean Chemical Society
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• 제14권4호
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• pp.476-480
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• 1993

The ab initio calculations were performed on ClO and $ClO^+$ using the configuration interaction and M${\phi}$ller-Plesset methods of several different levels of approximation. Three different basis sets, 66 contracted Gaussian-type orbitals,6-31$G^*$ and 6-311$G^*$, were employed in this calculation. The results of calculation were compared with the experimental values of ClO. The values from the calculation with 66cGTO basis set gave excellent agreement with the experimental values. The spectroscopic constants of $ClO^+$ were also predicted.