• Bulletin of the Korean Chemical Society
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• v.4 no.5
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• pp.208-211
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• 1983

Kinetic studies of nucleophilic substitution reactions of para-substituted benzylchlorides with anilines were conducted in a range of MeOH-MeCN mixtures at $55.1^{\circ}C$. Hammett ${\rho}_C$, ${\rho}_N$ values and Bronsted ${\beta}$ values were determined, in other to examine the transition state variations caused by changes in nucleophiles, substituents and solvents properties (${\pi}^{\ast}$ and ${\alpha}$). Applications of potential energy surface (PES) and quantum mechanical (QM) models of transitheion state characterization lead us to conclude that the reaction proceeds via the dissociative $S_N2$ mechanism.

• Educational Technology International
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• v.24 no.1
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• pp.53-80
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• 2023

This study investigates faculty support for quality assurance in online education, and offers suggestions for its improvement based on feedback from Instructional Design (ID) staff working at a public university in the U.S. Qualitative research using semi-structured interviews was conducted with seven ID staff in order to examine their perceptions regarding faculty support related to quality assurance in online education. The results of the data analysis indicate that four types of faculty support-quality assurance reviews using Quality Matter (QM) standards, templates, individual consultations with ongoing support, and monitoring-were offered for faculty. Faculty support for quality assurance in online education could be improved by developing specific quality assurance standards, recruiting external experts, examining learning effects, developing a quality assurance management system, and sharing documents among ID staff. This study highlights the necessity of quality assurance in online education and provides cases of faculty support in a real higher education setting.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.40 no.4
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• pp.78-86
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• 2017

The new businesses started by the companies usually results in being unsuccessful. The main reasons for that are either aiming targeting wrong customers, unsatisfaction of customers' requesting quality standards, or taking wrong actions against the competitors in the market. Therefore, companies should aim the targets for the newly developing products based on the fulfilling values for the customers when they start the new businesses, and should take good cares for risk managements at the each step of the new business to prevent the failure in advance. In addition to that, the companies starting new businesses not only need to take the customers attributes (CA) into account, but they also should apply the new technologies as one system to initiate a new business to satisfy the basic wants of the customers. This article suggests the New Product Development Pursuing Model using the Indicative Planning methodology and the Quality Management tools. The New Product Development Pursuing Model would be completed by the following steps as below; 1. Drawing the CTQ (Critical To Quality) for setting up the new product development objectives by : i) using the VOC (Voice Of Customers) obtained by the QFD (Quality Function Deploypment) if the market is mature, ii) applying AHP (Analytic Hierarchy Process) to information in the QIS (Quality Information System) if the market is unmature to get enough need information of the customers. 2. Risk Management in NPD : The NPD pursuing model consisted of the IP (indicative planning) is suggested not by the process of top-down-way mandatory planning process, but by the tools used in the administrative science and economic fields, namely by governance. The companies could apply innovative methodology for new products development processes to fulfil the customers satisfaction in the fields, through the CA (Contingency Approach) of the NPD (New Product Development) process.

• KSBB Journal
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• v.17 no.1
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• pp.100-105
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• 2002

N-acetyl-D-glucosamine oligosaccharides [(GlcNAc)n] whose degree of polymer-ization is from one to ten (n=1-10) were fractionated by column chromatography on CM-Sephadex. Electro dialysis from a partially deacetylated chitosan hydrolysate prepared crudely with the N-acetyl-D-glucosaminidase(chitinase) and exo-N, N'-diacetylchito-biohydrolase(chitobiase) of Serratia marcescens QM B1466. Reducing sugar compositions and sequences of the N-acetyl-glucosamine oligosaccharides were identified by N-acetylation, randomly cleavage with chitinase and ego-splitting with chitobiase. N-acetyl-glucosamine heterochitooligosaccharides with glucosamine oligosaccharides, (GlcN)n at the reducing end residues together with $(GlcN)_1\sim(GlcN)_4$ were detected. Separation was accomplished by prefractionation with election by 0 to 1.0 M NaCl gradient solution. $(GlcNAc)_1 =4.25%,\; (GlcNAc)_2=4.49%,; (GlcNAc)_3=11.1%,\; (GlcNAc)_4=2.5%,$$ $(GlcNAc)_{5}$=0.64%, $(GlcNAc)_{6}$=2.12% and $(GlcNAc)_{7}$=1.21%, respectively, were crystallized after electrodialysis and lyophilization Each N-acetyl-D-glucosamine oligosaccharides content were detected by HPLC.

• Korean Journal of Poultry Science
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• v.50 no.4
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• pp.261-266
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• 2023

The skeletal muscles of livestock play a crucial role as protein sources for humans, and the consumption of poultry meat is steadily increasing worldwide. Numerous genes, including myogenic regulatory factors, are involved in myogenesis, and precise regulation of them is essential. In this study, genes specifically expressed in muscles were selected, and their promoters were cloned and analyzed. The analysis of gene expression in various tissues of animals revealed that many genes exhibited specific expression patterns in skeletal muscles, with TNNT3, TNNC2, and MYF6 genes showing similar patterns in poultry. The promoter regions of three genes were amplified by polymerase chain reaction to sizes of 1.2 kb, 1.03 kb, and 1.43 kb, respectively. These fragments were then inserted at the front of the enhanced green fluorescent protein gene in vectors. It was confirmed that the sequences of three promoters closely matched the chicken genome sequences. Upon introducing vectors with each promoter into QM7 quail muscle cells, all three promoters successfully induced the expression of the green fluorescent protein. The brightness of the green fluorescence in each promoter was approximately seven times dimmer compared to the control, CMV-IE promoter. It is predicted that more than 230 transcription factors can bind to each promoter, especially various transcription factors expressed in muscles, including myogenic regulatory factors such as MYF5, MYOD, and MYOG. These promoters can be valuable for studying gene expression in poultry muscle cells, and further research is needed to precisely investigate the regulatory region of gene expression in promoters.

• Proceedings of the KIEE Conference
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• 2004.07c
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• pp.1624-1626
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• 2004

This study was to measure the minuteness structure, piezoelectric properties of (0.3-x)PMN- xPSS -0.7PZT+0.5[wt%]NiO+0.5(wt%)$MnO_2$ (x=0.05, 0.10, 0.15, 0.20, 0.25)ceramics according to sintering temp- erature and PSS(mol%) after manufacturing the specimens with a general method. the results of this study were gotten such as follows. The crystal structure of ceramic has the rombohedral structure in XRD. It appeared that addition of Ni, Mn additive was helpful to the formation of stable structure. The electrome- chanical coupling coefficient(kp) showed good properites on the whole, showed its maximum value 25.94[%] in specimens sintered at 1100[$^{\circ}C$], x=0.25mol. The mechanical quality coefficient(Qm) showed its maximum value 272.42 in specimens sintered at 1150[$^{\circ}C$], x=0.05mol. and was decreased by increasing PSS[mol%] The temperature coefficient of the resonant frequency(TCFr) showed stable properties in all sintering temperature with x=0.05mol. Especially good stability of 0.0054[%/$^{\circ}C$] showed in specimens sintered at 1100$^{\circ}C$, x=0.05mol.

• Bulletin of the Korean Chemical Society
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• v.29 no.8
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• pp.1499-1504
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• 2008

Pyrazine derivatives bind to b-RAF receptor which is important in cancer therapy. The ligand-receptor interactions have been studied by comparative molecular field analysis (CoMFA) and molecular docking methods. Applying conventional ligand-based alignment schemes for the whole set was not successful. However, QM and DFT results suggested that some ligands have electrostatic interaction while others have steric interactions. On the basis of these results, we divided the dataset into two subsets. Electrostatic effect was found to be important in one set while steric effect for the other. Best docking modes were obtained for each subset based on the available crystal structure. These receptor-guided CoMFA models propose an interesting possibility which is difficult to obtain otherwise. i.e., in one binding mode the electrostatic interaction plays a key role for one subset ($q^2$ = 0.46, $r^2$ = 0.98), while in another binding mode steric effect is important with another subset ($q^2$ = 0.43, $r^2$ = 0.74).

• Proceedings of the IEEK Conference
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• 2004.08c
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• pp.482-485
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• 2004

We fabricated a hybrid bulk/fully depleted silicon on insulator (FDSOI) complementary metal oxide semiconductor (CMOS) active pixel image sensor. The active pixel is comprised of reset and source follower transistors on the SOI seed wafer, while the pinned photodiode and readout gate and floating diffusion are fabricated on the SOI handle wafer after the removal of the buried oxide. The source of dark current is eliminated by hybrid bulk/FDSOI pixel structure between localized oxidation of silicon (LOCOS) and photodiode(PD). By using the low noise hybrid pixel structure, dark currents qm be suppressed significantly. The pinned photodiode can also be optimized for quantum efficiency and reduce the noise of dark current. The spectral response of the pinned photodiode on the SOI handle wafer is very flat between 400 nm and 700 nm and the dark current that is higher than desired is about 10 nA/cm2 at a $V_{DD}$ of 2 V.

• Journal of the Korean Chemical Society
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• v.41 no.1
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• pp.22-46
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• 1997

Kinetic studies on nucleophilic substitution reaction of phenacyl bromide and phenacyl chloride with pyridines were conducted at 25℃ and 35℃ in methanol-acetonitrile solvents mixtures. It was shown that the reaction proceeds via an SN2 reaction mechanism based on the transition state parameters, ΔH≠ and ΔS≠ and Bro nsted β values. Quantum mechanical model predicted a product-like transition state, where bond-formation is much more progressed than bond breaking, upon changing the leaving group to that with a better leaving ability.

• Journal of the Korean Ceramic Society
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• v.36 no.10
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• pp.1108-1114
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• 1999

Microstructure and electrical properties of ZnO-doped (0-5 mol%) 0.05 Pb(Mn1/3Sb2/3)O3-0.95 PZT ceramics were investigated. Sintering temperature was decreased to 100$0^{\circ}C$ due to eutetic reaction between PbO and ZnO. Grain-size increased up to adding 1mol% ZnO and then decreased. Compositions of grain and grain-boundary were investigated by WDS. Lattice parameter was decreased with ZnO addition. Density increased with ZnO addition and reached to the maximum of 7.84(g/cm2) at 2 mol% ZnO. The effect of ZnO on electrical properties of PMS-PZT was investigated. At 3mol% ZnO addition electromechanical coupling factor(kp) was about 50% and relative dielectric constant($\varepsilon$33/$\varepsilon$0) was 997 Mechanical quality factor(Qm) decreased with ZnO addition. Lattice parameters and tetragonality(c/a) were measured to investigate relationship between the electric properties and substitution of Zn2+. At 3 mol% ZnO tetragonality was maximiged at c/a=1.0035 Curie temperature (Tc) decreased slightly with ZnO addition.