• Journal of the Korean Chemical Society
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• v.56 no.4
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• pp.468-472
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• 2012

Efficient one-pot microwave-assisted synthesis of various benzo-[1,4]-oxazinones via Smiles rearrangement is described. Treatment of 2-chloroacetamide, substituted 2-chlorophenols and cesium carbonate in MeO-PEG-OMe (2,000) as solvent afforded the corresponding benzo-[1,4]-oxazinones and 1H-pyrido[2,3-b][1,4]-oxazin-2-(3H)-one as moderate yield.

• Nuclear Engineering and Technology
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• v.33 no.5
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• pp.526-538
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• 2001

Fatigue tests in air and in room temperature water were performed to obtain comparable data and stable crack measuring conditions. In air environment, fatigue crack growth rate was increased with increasing temperature due to an increase in crack tip oxidation rate. In room temperature water, the fatigue crack growth rate was faster than in air and crack path varied on loading conditions. In simulated light water reactor (LWR) conditions, there was little environmental effect on the fatigue crack growth rate (FCGR) at low dissolved oxygen or at high loading frequency conditions. While the FCGR was enhanced at high oxygen condition, and the enhancement of crack growth rate increased as loading frequency decreased to a critical value. In fractography, environmentally assisted cracks, such as semi-cleavage and secondary intergranular crack, were found near sulfide inclusions only at high dissolved oxygen and low loading frequency condition. The high crack growth rate was related to environmentally assisted crack. These results indicated that environmentally assisted crack could be formed by the Electrochemical effect in specific loading condition.

• Horticultural Science & Technology
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• v.35 no.2
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• pp.149-164
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• 2017

Next generation sequencing (NGS) technologies have led to the rapid accumulation of genome sequences through whole-genome sequencing and re-sequencing of crop species. Genomic resources provide the opportunity for a new revolution in plant breeding by facilitating the dissection of complex traits. Among vegetable crops, reference genomes have been sequenced and assembled for several species in the Solanaceae and Cucurbitaceae families, including tomato, pepper, cucumber, watermelon, and melon. These reference genomes have been leveraged for re-sequencing of diverse germplasm collections to explore genome-wide sequence variations, especially single nucleotide polymorphisms (SNPs). The use of genome-wide SNPs and high-throughput genotyping methods has led to the development of new strategies for dissecting complex quantitative traits, such as genome-wide association study (GWAS). In addition, the use of multi-parent populations, including nested association mapping (NAM) and multiparent advanced generation intercross (MAGIC) populations, has helped increase the accuracy of quantitative trait loci (QTL) detection. Consequently, a number of QTL have been discovered for agronomically important traits, such as disease resistance and fruit traits, with high mapping resolution. The molecular markers for these QTL represent a useful resource for enhancing selection efficiency via marker-assisted selection (MAS) in vegetable breeding programs. In this review, we discuss current genomic resources and marker-trait association analysis to facilitate genome-assisted breeding in vegetable species in the Solanaceae and Cucurbitaceae families.

• Applied Chemistry for Engineering
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• v.28 no.2
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• pp.165-170
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• 2017

An efficient synthetic process for bio-based adipic acid, a monomer for nylon 66, was developed from galactose. Galactaric acid, prepared from a mild oxidation of galactose using a Pt catalyst, was successfully converted to muconate, a key intermediate for adipic acid, by an efficient microwave-assisted DODH (deoxydehydration) reaction. The high efficiency of the microwave-assisted reaction greatly reduced the overall reaction time to 30 min. and resulted in an excellent yield of 97% of muconate. The catalytic hydrogenation of muconate followed by the acidic hydrolysis successfully produced the desired adipic acid in high purity after recrystallization.

• Journal of the Korean Society for Precision Engineering
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• v.29 no.11
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• pp.1214-1220
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• 2012

Vibration assisted cutting (VAC) is one of the promising methods for precision machining, which has been normally equipped with piezoelectric materials. In this paper, a feasibility of applying magnetostrictive materials to VAC as a cutting device instead of piezoelectric materials was studied. For this, the vibrational characteristics of a magnetostrictive material was investigated with respect to a coil design, a preload, and the effects of a biasing and an exciting magnetic fields. The output strain of a magnetostrictive material is restricted due to an increasing inductive impedance as the exciting frequency increases and the heat of coil, etc. Through the experimental results, it was found that the biasing and the exciting magnetic field affected the output performance significantly but not the preload. In conclusion, the magnetostrictive material could be used only in the low frequency range but not a good candidate for high frequency actuating application.

• Journal of the Korean Society for Precision Engineering
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• v.31 no.2
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• pp.119-123
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• 2014

Recently, laser processing technologies have been developed in many different industrial fields. The laser processing technologies are widely being applied such as laser assisted machining, cladding, heat treatment and coating. In the laser modules of the laser assisted machining system, laser lens is very important for accuracy and productivity of product. As the laser beam size, shape and focusing distance change, heat input energy of preheating point can be changed, the laser module of the laser assisted machining system should be equipped with various lenses differing beam size, beam shape and focusing distance. In this study, the rotary and linear laser modules are suggested. The finite element analysis is carried out to certify the static and dynamic stabilities of the developed laser modules. Finally, the rotary and linear laser modules have been fabricated successfully using the analysis results.

• Journal of Trauma and Injury
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• v.30 no.3
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• pp.87-90
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• 2017

Purpose: Nowadays, Video-Assisted Thoracic Surgery (VATS) is widely used for its benefits, low post-operative pain, excellent anesthetic result and complete visualization of intrathoracic organs. Despite of these advantages, VATS has not yet been widely used in trauma patients. In this study, we aimed to investigate the usefulness of VATS in the chest trauma area. Methods: From January 2016 to December 2016, 203 patients underwent surgical treatment for chest trauma. Their medical records were analyzed retrospectively. Results: Eleven patients underwent thoracic surgery by VATS. Six patients were unstable vital sign in the emergency room. Two patients underwent emergency surgery and the rest patients underwent planned surgery. The common surgeries were VATS hematoma evacuation and wedge resection. There was no conversion to thoracotomy. The surgery proceeded without any problems for all patients. Conclusions: VATS would be an effective diagnostic and therapeutic modality in chest trauma patients. It can be applied to retained hemothorax, persistent pneumothorax, suspicious diaphragm injury and even coagulation of bleeder.

• Mass Spectrometry Letters
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• v.9 no.2
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• pp.46-50
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• 2018

The effects of temperature and acetonitrile (ACN) concentration on microwave-assisted weak-acid hydrolysis of proteins were investigated. Myoglobin was hydrolyzed for 1 h using 2% formic acid and a microwave with different concentrations of ACN (0, 5, and 10%) at various temperatures (50, 60, 70, 80, 90, and $100^{\circ}C$). The numbers of peptides identified with each concentration of ACN were the same for each temperature. The greatest number of peptides (18 total) was obtained with hydrolysis at $100^{\circ}C$, and 6 of these were a result of additional removal of aspartic acid at the C-terminus. Hydrolysis at $80^{\circ}C$ resulted in 13 peptides, of which only 1 was generated by the additional removal of aspartic acid, and 12 were observed with hydrolysis at $100^{\circ}C$. Our results demonstrate that microwave-assisted weak-acid hydrolysis of proteins can be performed successfully at $80^{\circ}C$, which could be beneficial for limiting side reactions and generating larger peptide sequences.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.19 no.5
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• pp.223-227
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• 2009

$BaCO_3$ crystals with various morphology were prepared using precipitation, hydrothermal and ligand-assisted methods. An irregular structure of $BaCO_3$ microparticle was obtained by simple precipitation method from $Ba(NO_3)_2$ and $Na_2CO_3$ in aqueous solution. Hexagonal pyramidals of $BaCO_3$ were synthesized using a hydrothermal method between $Ba(NO_3)_2$ and urea. Hexagonal rods of $BaCO_3$ were also synthesized using the ligand-assisted hydrothermal method. The aspect ratio of $BaCO_3$ hexagonal rods was increased with the concentration of ligand.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.24 no.1
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• pp.60-71
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• 2017

Purpose: The purpose of this study was to develop video assisted education on bowel preparation for colonoscopy (VEBPC) and use a snartphone to evaluate effects of the VEBPC. Methods: Adult patients who were scheduled for colonoscopy were recruited from a university general hospital and randomly assigned to three groups. Group 1 (n=30) watched the video using a computer set in the endoscope consulting room. Group 2 (n=29) watched it using a smartphone, and group 3, the control group (n=29) received education with existing instructions at the reservation-reception desk. Participants were evaluated on knowledge on taking bowel preparation agents and diet, compliance on taking bowel preparation agents and diet, satisfaction with education, and actual level of bowel preparation. Results: Group 1 and 2 showed significantly (p<.001) higher scores for knowledge, compliance, and satisfaction compared to the control group. However, in post-hoc test analyses there were no significant differences in these variables between group 1 and 2. No significant difference was found in the actual level of bowel preparation among the three groups. Conclusion: Findings from this study show that VEBPC using smartphone is a better option than existing educational methods. However, replication studies are necessary to confirm these findings.