• Journal of the Korean Chemical Society
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• v.51 no.4
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• pp.361-364
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• 2007

A one-pot Beckmann rearrangement for the preparation of amides from ketones is described using the silica sulfuric acid under Microwave irradiation. Advantages of this method are regioselectivity with high yields in a simple operation and short reaction time, in which the mole ratio of acid and ketone was 1:2 and it should be greener than the currently used systems.

• Journal of the Korean Operations Research and Management Science Society
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• v.33 no.2
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• pp.75-86
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• 2008

A remarshalling is one of the operational strategies considered importantly at a port container terminal for the fast ship operations and heighten efficiency of slacking yard. The remarshalling rearranges the containers scattered at a yard block in order to reduce the transfer time and the rehandling time of container handling equipments. This Paper deals with the rearrangement problem, which decides to where containers are transported considering time value of each operations. We propose the mixed integer programming model minimizing the weighted total operation cost. This model is a NP-hard problem. Therefore we develope the heuristic algorithm for rearrangement problem to real world adaption. We compare the heuristic algorithm with the optimum model in terms of the computation times and total cost. For the sensitivity analysis of configuration of storage and cost weight, a variety of scenarios are experimented.

• Korean Journal of Computational Design and Engineering
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• v.16 no.3
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• pp.207-215
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• 2011

Due to its large size, a ship is first divided into scores of blocks and then each block is constructed through various shops, such as the assembly shop, the painting shop, and the outfitting shop. However, each block may not be directly moved to the next shop and may be temporarily laid on a block stockyard because the working time in each shop is different. If blocks are laid on the block stockyard without any planning, the rearrangement of the blocks by a transporter are required because the blocks have the different in and out time. In this study, an optimal layout method based on the genetic algorithm was proposed in order to minimize the rearrangement of the blocks in the block stockyard. To evaluate the applicability of the proposed method, it was applied to a simple layout problem of the block stockyard.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.46 no.5
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• pp.19-25
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• 2009

In this paper, the constellation rearrangement method for retransmission based on Chase combining, is introduced. And the effectiveness of the recommended constellation rearrangements is analyzed with statistics. Their performance for turbo-coded or convolutional coded bit streams is evaluated with simulation under additive white Gaussian noise environment.

• Bulletin of the Korean Chemical Society
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• v.31 no.9
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• pp.2479-2482
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• 2010

Using a pinhole-type glass nozzle equipped for a corona-excited supersonic expansion (CESE), precursor 2,6-dichlorotoluene seeded in a large amount of inert carrier gas helium was discharged to produce jet-cooled but electronically excited benzyl-type radicals. The visible vibronic emission spectrum was recorded with a long-path monochromator to observe vibronic bands in the $D_1{\rightarrow}D_0$ electronic transition of benzyl-type radicals. The spectral analysis revealed the generation of not only the 2,6-dichlorobenzyl radical as a typical product, but also the o-chlorobenzyl radical as an unexpected species, which indicates the possible molecular rearrangement in eliminating a chlorine atom from the benzene ring. A possible mechanism is proposed for the formation of the o-chlorobenzyl radical from the precurs or in the gas phase.

• Bulletin of the Korean Chemical Society
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• v.34 no.1
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• pp.54-58
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• 2013

Licochalcones, derived from the dried roots of Glycyrrhiza inflata, have been reported to show various biological activities including antitumor, antiparasitic, antileishmanial, antioxidative, superoxide scavenging, antibacterial, and PTP1B activity. Licochalcone D has an allyl group on ring A instead of ring B, however, most other natural licochalcones possess the group on ring B. Total synthesis of licochalcone D has not been reported even possessing the strongest anti-inflammatory activity. Therefore, the first total synthesis of licochalcone D has been developed by using water-accelerated [3,3]-sigmatropic rearrangement method.

• Bulletin of the Korean Chemical Society
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• v.34 no.2
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• pp.585-589
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• 2013

Optically active N-benzyl-2-methyl-2H-benzo[b][1,4]oxazin-3(4H)-ones and N-benzyl-2-methyl-2H-benzo[b][1,4]thiazin-3(4H)-ones with potential synthetic and pharmacological interest were prepared via Smiles rearrangement in conventional as well as microwave irradiation conditions in one-pot from inexpensive (S)-2-chloropropionic acid. Most of the compounds displayed good inhibition against Gram positive bacteria and fungi in the antibiotic test.

• Bulletin of the Korean Chemical Society
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• v.34 no.2
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• pp.394-398
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• 2013

An efficient process for the synthesis of N-azaaryl anilines via Smiles rearrangement as a tool. A variety of N-azaaryl anilines were generated by the reaction of substituted phenols, substituted anilines, aminopyridines and chloroacetyl chloride or pyridols, under base condition in good to excellent yields.

• Aerospace Engineering and Technology
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• v.9 no.1
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• pp.98-105
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• 2010

Fast Fourier Transform is the fast implementation of Discrete Fourier Transform, which deletes periodic operation of DFT. According to the definition, radix-2 FFT can be implemented byre cursive call which divides the input signal points into 2 signal points. Because of its time-consuming stack-copy operation, this recursive method is very slow. To overcome this drawback, butterfly operation with signal rearrangement was devised. Based on the ideas of signal rearrangement and butterfly operation, this paper applies the signal rearrangement method to the Radix-3 FFT and checks the validity of this method.

• Bulletin of the Korean Chemical Society
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• v.19 no.4
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• pp.444-449
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• 1998

The kinetics of the formation of triplex $poly(dA){\cdot}[poly(dT)]_2$ from poly(dA)·poly(dT) and poly(dT) is examined by various optical spectroscopic methods, including absorption, circular and linear dichroism (LD) spectroscopy. In the pseudo first order condition, where the poly(dT) concentration is kept lower than that of duplex, the association of the poly(dT) is enhanced by the presence of ethidium; the rate constant is proportional to the amount of ethidium in the mixture. When the concentration of the duplex and the single strand is the same, a spectral change is explained by double exponential curves, indicating that at least two steps are involved, the fast association and slow rearrangement steps. In contrast to the pseudo first order kinetics, the association step in an equimolar condition is not affected by the presence of ethidium. In the rearrangement step, the magnitude of LD decreases with an increase in ethidium concentration, suggesting that the bending of polynucleotide around the intercalation site occurs in the rearrangement step.