• Journal of the Korean Society of Industry Convergence
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• v.25 no.5
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• pp.909-915
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• 2022

In this paper, a robot automation technology for chemical tank lorry unloading is presented. Handling chemical coupler between tank lorry and ACQC system may be hazardous or toxic to human operators, therefore robot automation is essential. Due to tight tolerance between couplers, even small pose error may result in very large internal force. In order to resolve the problem, compliance between male and female couplers should be introduced with 6-axis compliance device with F/T sensing. The proposed robot automation system consists of a collaborative robot, 6-ax is compliance device with F/T sensing, linear gripper, and robot vision. The position/force control algorithm and experimental results for assembling chemical couplers are presented.

• Journal of the Korean Society of Industry Convergence
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• v.26 no.4_1
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• pp.545-551
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• 2023

In this paper, a robot automation methodology for chemical drum assembly in semiconductor industries are presented. Robot automation is essential to resolve safety issues in which operators are directly or indirectly exposed to chemicals or fumes in assembling dispense heads on chemical drums. However, the chemical drum assembling process involves complex and difficult tasks, such as mating male/female keycodes and fastening screws with large-diameter, which may be very difficult to be performed by a single-arm robot with a commercial rigid F/T sensor. In order to solve the problems, a method for assembling a chemical drum using dual-arm collaborative robot system, compliance F/T sensor, robot vision and gripper is presented.

• Applied Chemistry for Engineering
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• v.31 no.1
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• pp.36-42
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• 2020

In order to investigate the effect of the oxidation process on thermal properties of the pitch, the oxidized pitch was prepared by changing the oxidation temperature. Thermal properties of the pitch were analyzed using thermogravimetric analysis (TGA), and it divided into three sections as A (25~100 ℃), B (250~550 ℃) and C (550~800 ℃) by derivative thermogravimetry (DTG) graph behavior. In the A section, the was reduced because the moisture contained in the pitch was removed. In the B section, as the oxidation temperature increased, the thermal stability of the pitch is improved. Because the degree of aromaticity and molecular weight of the pitch increased with increasing oxidation temperature. In contrast, the results of the C section were shown opposite of B section. Because the introduced C-OH, C-O-C, and C=O bonds were decomposed, and the resulting oxygen compounds induced the combustion reaction of the pitch.

• Journal of Microbiology and Biotechnology
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• v.19 no.1
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• pp.72-77
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• 2009

Here, we demonstrate that the overexpression of the GroELS chaperone system, which assists the folding of intracellular proteins and prevents aggregation of its biological targets, can enhance the thermotolerance of Escherichia coli strains and facilitate the production of recombinant protein under thermal stress. The overexpression of GroELS led to an about 2-fold higher growth rate of E. coli XL-1 blue than control at $45^{\circ}C$ and induced the growth of the strain even at $50^{\circ}C$, although the growth was not sustained in the second-round culture. The effect of GroELS overexpression was also effective on other E. coli strains such as JM109, $DH5{\alpha}$, and BL21. Finally, we have shown that coexpression of GroELS allows us to produce recombinant protein even at $50^{\circ}C$, a temperature at which the protein production based on E. coli is not efficient. This study indicates that the employment of the GroELS overexpression system can expand the range of environmental conditions for E. coli.

• Biotechnology and Bioprocess Engineering:BBE
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• v.11 no.6
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• pp.530-537
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• 2006

Recently isolated, Pseudomonas putida SN1 grows on styrene as its sole carbon and energy source through successive oxidation of styrene by styrene monooxygenase (SMO), styrene oxide isomerase (SOI), and phenylacetaldehyde dehydrogenase. For the production of (S)-styrene oxide, two knockout mutants of SN1 were constructed, one lacking SOI and another lacking both SMO and SOI. These mutants were developed into whole-cell biocatalysts by transformation with a multicopy plasmid vector containing SMO genes (styAB) of the SN1. Neither of these self-cloned recombinants could grow on styrene, but both converted styrene into an enantiopure (S)-styrene oxide (e.e. > 99%). Whole-cell SMO activity was higher in the recombinant constructed from the SOI-deleted mutant (130 U/g cdw) than in the other one (35 U/g cdw). However, the SMO activity of the former was about the same as that of the SOI-deleted SN1 possessing a single copy of the styAB gene that was used as host. This indicates that the copy number of styAB genes is not rate-limiting on SMO catalysis by whole-cell SN1.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.55 no.4
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• pp.431-436
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• 2022

For the safety assessment of microbiological and chemical hazards in katsuobushi, fifteen samples of katsuobushi were purchased from supermarkets. The contamination levels of total viable bacteria, coliforms, Escherichia coli, and nine pathogenic bacteria [Staphylococcus aureus, Salmonella spp., Listeria monocytogenes, Bacillus cereus, Vibrio parahaemolyticus, Clostridium perfringens, Enterohemorrhagic E. coli (EHEC), Yersinia enterocolitica and Campylobacter jejuni/coli] were quantitatively or qualitatively assessed. Additionally, the heavy metals (total and methyl mercury) content, radioactivity (¹³¹ I, ¹³⁴ Cs⁺ and ¹³⁷ Cs) were quantitatively assessed. Microbial and chemical analyses were performed using standard methods in Korean food code. The contamination level of total viable bacteria was 2.70 (1.18-4.42) log CFU/g. Coliforms, E. coli and S. aureus were not detected in any samples. Other eight pathogenic bacteria were negative in all samples. The contamination levels of total and methyl mercury were 0.366 (0.227-0.481) and 0.120 (0.002-0.241) mg/kg, respectively. In addition, radioactivity was not detected in any samples. The results will be helpful in revitalizing domestic use and boosting exports of katsuobushi because the microbiological and chemical safety of katsuobushi has been assured. Furthermore, the results may be used as a basis for performing chemical and microbial risk assessments of katsuobushi.

• Journal of the Korean Professional Engineers Association
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• v.33 no.5
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• pp.28-32
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• 2000

It is about time for Korean plant engineering industry to evaluate what they have achieved in the past and to foresee how this industry will change in the future. Since the IMF infection in the late 1997, Korean engineering industry has become to realize how important it is to formulate plans and solutions in order to be successful in the EPC industry. Korean plant engineering has accomplished remarkable growth in terms of its sales volumes and sizes of petrochemical & refinery plants they have executed, but unfortunately they have not done a nice job of generating sufficient profits. Many Korean engineering companies have carried out million and billion dollars of "projects" where they unfortunately suffered deficits, and as a result, some companies actually went deteriorated and were merged, and acquired by bigger companies. Based on above philosophy, the ten(10) key factors are suggested regarding a proposal for role and mission of chemical engineering professional engineer in plant engineering industry in the 21\\\" century.

• Bulletin of the Korean Chemical Society
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• v.9 no.6
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• pp.400-402
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• 1988

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.39 no.4
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• pp.38-44
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• 2007

In order to utilize unsorted ONP, which contains leaflets (printed coated papers), to produce pulp mold, optimum conditions for a repulping process were investigated with a laboratory high consistency pulper. It was concluded that medium or high consistency pulping is necessary to accelerate the rate of deflaking of unsorted ONP. Considering flake content, fines content and pulping energy, the optimum conditions for the laboratory Helico pulper were 11% of repulping concentration and 3 min of repulping time. The repulping temperature shall be at least $30^{\circ}C$. Aging of paper slows down the rate of de flaking but in an actual pulp molding process its effect could be negligible.

• Biotechnology and Bioprocess Engineering:BBE
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• v.10 no.3
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• pp.242-247
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• 2005

Caseinomacropeptide (CMP) is a glycopeptide of 64 amino acid residues derived from the C-terminal of mammalian milk K-casein. Recently, human CMP (hCMP) was produced from the recombinant yeast Saccharomyces cerevisiae. In this study, the antiobesity activity of the recombinant hCMP (rhCMP) was investigated in vivo using Sprague-Dawley rats. The rhCMP did not affect the rats fed with a normal fat diet (fat content, $5.0\%$), but decreased the body weight gain of the rats fed with a high fat diet (fat content, $20\%$) by up to $19\%$. Autopsies revealed that the weights of the liver, kidney and adipose tissues decreased when the rats were given the rhCMP, which also reduced the lipid concentrations in the plasma and liver, but enhanced the fecal excretion of lipids. These results suggest that rhCMP prevent the accumulation of lipid by stimulating its fecal excretion, so could be used as a food supplement to alleviate the obesity problem caused by a high fat diet.