• KSBB Journal
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• v.27 no.4
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• pp.232-236
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• 2012

Comparative liquid chromatographic enantiomer separation of ${\alpha}$-amino acids, their esters and primary amino compounds was performed using two chiral stationary phases (CSPs) prepared by covalently bonding (+)-(18-crown-6)-2,3,11,12-tetracarboxylic acid (18-C-6-TA) of the same chiral selector. In general, the separation factors and resolution factors for these analytes on CSP 1 were greater than on CSP 2, while these capacity factors on CSP 2 were quite greater than on CSP 1. Except for leucine methyl ester and phenylalanine methyl ester, the elution orders of all analytes including ${\alpha}$-amino ${\alpha}$-alkyl acids and phenylglycine alkyl esters on CSP 1 are identical to those on CSP 2. This study showed that different connecting structures for these two CSPs might influence their ability to resolve the analytes depending on their structures related to the chiral recognition mechanism.

• Bulletin of the Korean Chemical Society
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• v.34 no.10
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• pp.2978-2982
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• 2013

A doubly tethered $N-CH_3$ amide chiral stationary phase (CSP 4) based on (+)-(18-crown-6)-2,3,11,12-tetracarboxylic acid was applied to the resolution of an antiarrythmic agent, tocainide, and its analogues and the chromatographic resolution results were compared with those on a singly tethered N-H amide CSP (CSP 1), a singly tethered $N-CH_3$ amide CSP (CSP 2) and a doubly tethered N-H amide CSP (CSP 3) under an identical aqueous mobile phase condition. CSP 4 was found to be generally better than other CSPs in terms of the separation factors (${\alpha}$) and resolutions (RS). The retention times of analytes denoted by the retention factors ($k_1$) on CSP 4 were quite long compared to those on other CSPs because of the improved lipophilicity of CSP 4. The long retention times of analytes on CSP 4 were successfully controlled by the addition of a small amount of ammonium acetate to aqueous mobile phase without hurting the chiral recognition efficiency. The variation of the content and type of organic and acidic modifier in aqueous mobile phase was found not to change the chiral recognition efficiency significantly.

• Bulletin of the Korean Chemical Society
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• v.31 no.6
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• pp.1551-1554
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• 2010

Two diastereomeric chiral stationary phases (CSPs) were applied to the liquid chromatographic resolution of various racemic ${\alpha}$-amino methyl esters, ${\alpha}$-amino N,N-diethylamides and ${\alpha}$-amino N-propylamides. The CSP incorporating (R)-3,3'-diphenyl-1,1'-binaphtyl and (R,R)-tartaric acid unit as chiral barriers did not show any chiral recognition. In contrast, the CSP incorporating (R)-3,3'-diphenyl-1,1'-binaphtyl and (S,S)-tartaric acid unit as chiral barriers was found to show excellent chiral recognition especially for the two enantiomers of ${\alpha}$-amino N-propylamides. Some of ${\alpha}$-amino methyl esters and ${\alpha}$-amino N,N-diethylamides were also resolved on the CSP incorporating (R)-3,3'-diphenyl-1,1'-binaphtyl and (S,S)-tartaric acid unit. From these results it was concluded that the two chiral units composing the diastereomeric CSPs can show "matched" or "mismatched" effect on the chiral recognition according to their absolute stereochemistry.

• The Journal of Engineering Research
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• v.6 no.2
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• pp.11-22
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• 2004

A distributed constraint satisfaction problem (distributed CSP) is a constraint satisfaction problem(CSP) in which variables and constraints are distributed among multiple automated agents. ACSP is a problem to find a consistent assignment of values to variables. Even though the definition of a CSP is very simple, a surprisingly wide variety of AI problems can be formalized as CSPs. Similarly, various application problems in DAI (Distributed AI) that are concerned with finding a consistent combination of agent actions can be formalized as distributed CAPs. In recent years, many new backtracking algorithms for solving distributed CSPs have been proposed. But most of all, they have common drawbacks that the algorithm assumes the priority of agents is static. In this thesis, we establish a basic algorithm for solving distributed CSPs called dynamic priority search algorithm that is more efficient than common backtracking algorithms in which the priority order is static. In this algorithm, agents act asynchronously and concurrently based on their local knowledge without any global control, and have a flexible organization, in which the hierarchical order is changed dynamically, while the completeness of the algorithm is guaranteed. And we showed that the dynamic priority search algorithm can solve various problems, such as the distributed 200-queens problem, the distributed graph-coloring problem that common backtracking algorithm fails to solve within a reasonable amount of time. The experimental results on example problems show that this algorithm is by far more efficient than the backtracking algorithm, in which the priority order is static. The priority order represents a hierarchy of agent authority, i.e., the priority of decision-making. Therefore, these results imply that a flexible agent organization, in which the hierarchical order is changed dynamically, actually performs better than an organization in which the hierarchical order is static and rigid. Furthermore, we describe that the agent can be available to hold multiple variables in the searching scheme.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2000.10a
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• pp.7-38
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• 2000

Performance, reliability, form factor drive flip chip use. BGAs and CSPs will provide stepping stone to FC DCA .Growing vendor infrastructure - Low cost, high density organic substrates -New generations of fluxes and underfills .Adhesives flip chip technology as a low cost flip chip alternatives -Low cost Au stud or Electroless Ni bumps -Reliable thermal cycling and electrical performance.

• Bulletin of the Korean Chemical Society
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• v.8 no.1
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• pp.45-47
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• 1987

After conversion to their 3,5-dinitrobenzoyl or 3,5-dinitroanilide derivatives, the enantiomers of a number of drugs may be chromatographically separated on various ${\alpha}$-arylalkylamine-derived chiral stationary phases (CSPs). While each CSP used in this study is useful, CSP 1 is best able to resolve the 3,5-dinitroanilide derivative of Ibuprofen while CSP 9 generally gives rather large ${\alpha}$ values for the resolution of 3,5-dinitrobenzoyl derivatives of the enantiomers of ${\beta}$-adrenergic blocking drugs.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.224.2-224.2
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• 2003

Pyrethroic acids are essential chiral intermediates of the pyrethroids, which account for about 25% of the world insecticide market and are found to be some of the most effective commercially available pesticides. It was demonstrated that polysaccharide-derived chiral stationary phases (CSPs) are very efficient for the separation of the enantiomers of pyrethroid acids. It was observed that the enantioseparation of pyrethroic methyl ester and ethyl derivatives was well accomplished on brush-type WhelkO-1. (omitted)

• International conference on construction engineering and project management
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• 2005.10a
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• pp.633-637
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• 2005

The paper presents a multifactor modelling of construction processes. There are three phases of the proposed extended procedure. Tools for these phases from chronometric test to verifying of the assumed model are indicated. Apart from the classic verification activities the method of artificial neural networks has been successfully applied. The paper presents the usage of these tools to model the process of assembly of structural corrugated steel plate structures.

• Bulletin of the Korean Chemical Society
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• v.32 no.spc8
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• pp.3017-3021
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• 2011

Two chiral stationary phases (CSPs) based on (3,3'-diphenyl-1,1'-binaphthyl)-20-crown-6 bonded covalently to silica gel were applied for the first time to the resolution of racemic vigabatrin and its analogue ${\gamma}$-amino acids and the resolution results were compared to those on the commercially available Crownpak CR(+) based on (3,3'-diphenyl-1,1'-binaphthyl)-20-crown-6 coated dynamically onto octadecylsilica gel. While vigabatrin was not resolved at all on Crownpak CR(+), it was resolved quite well on the two CSPs. Among four vigabatrin analogue ${\gamma}$-amino acids, only two were resolved on Crownpak CR(+), but three were resolved on the CSP (CSP 1) containing residual silanol groups and all of four were resolved on the CSP (CSP 2) containing residual silanol group-protecting n-octyl groups. The improved lipophilicity in CSP 2 was proposed to be responsible for its superiority to CSP 1 for the resolution of vigabatrin and analogue ${\gamma}$-amino acids. In addition, the composition of aqueous mobile phase was found to affect the chiral recognition behaviors for the resolution of vigabatrin and analogue ${\gamma}$-amino acids on CSP 2.

• The Plant Pathology Journal
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• v.33 no.2
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• pp.148-162
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• 2017

As a step towards discovering novel pathogenesis-related proteins, we performed a genome scale computational identification and characterization of secreted and transmembrane (TM) proteins, which are mainly responsible for bacteria-host interactions and interactions with other bacteria, in the genomes of six representative Burkholderia species. The species comprised plant pathogens (B. glumae BGR1, B. gladioli BSR3), human pathogens (B. pseudomallei K96243, B. cepacia LO6), and plant-growth promoting endophytes (Burkholderia sp. KJ006, B. phytofirmans PsJN). The proportions of putative classically secreted proteins (CSPs) and TM proteins among the species were relatively high, up to approximately 20%. Lower proportions of putative type 3 non-classically secreted proteins (T3NCSPs) (~10%) and unclassified non-classically secreted proteins (NCSPs) (~5%) were observed. The numbers of TM proteins among the three clusters (plant pathogens, human pathogens, and endophytes) were different, while the distribution of these proteins according to the number of TM domains was conserved in which TM proteins possessing 1, 2, 4, or 12 TM domains were the dominant groups in all species. In addition, we observed conservation in the protein size distribution of the secreted protein groups among the species. There were species-specific differences in the functional characteristics of these proteins in the various groups of CSPs, T3NCSPs, and unclassified NCSPs. Furthermore, we assigned the complete sets of the conserved and unique NCSP candidates of the collected Burkholderia species using sequence similarity searching. This study could provide new insights into the relationship among plant-pathogenic, humanpathogenic, and endophytic bacteria.