• Korean Chemical Engineering Research
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• v.49 no.6
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• pp.720-725
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• 2011

Gold catalysts supported on metal-oxides were prepared by co-precipitation using the various metal nitrates and chloroauric acid as precursors, and effect of water addition on the catalytic activity in CO oxidation was investigated. Among the various supported gold catalysts, Au/$Co_{3}O_{4}$ and Au/ZnO catalysts showed the excellent activity for CO oxidation. Water in the reactant gas had a negative effect on the oxidation activity over Au/$Co_{3}O_{4}$ catalysts and a positive effect on that over Au/ZnO, which means the activity depends strongly on the nature of support. It was also confirmed that no significant change in the particle size of gold was observed after reaction both in dry and wet conditions. This fact suggested that the deactivated catalyst due to a carbonate species could be regenerated by water addition in the reactant gas.

• Journal of KIISE
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• v.42 no.8
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• pp.1031-1038
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• 2015

The recent emergence of smart phones, wearable devices, and even the IoT concept made it possible for various objects to interact one another anytime and anywhere. Among many of such smart services, a smart home service typically requires a large number of sensors to recognize the residents' activities. For this reason, the ideas on activity recognition using the data obtained from those sensors are actively discussed and studied these days. Furthermore, plenty of sensors are installed in order to recognize activities and analyze their patterns via data mining techniques. However, if many of these sensors should be installed for IoT smart home service, it raises the issue of cost and energy consumption. In this paper, we proposed a new method for reducing the number of sensors for activity recognition in a smart environment, which utilizes the principal component analysis and clustering techniques, and also show the effect of improvement in terms of the activity recognition by the proposed method.

• Journal of Microbiology and Biotechnology
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• v.29 no.7
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• pp.1144-1154
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• 2019

There have been several studies regarding lichen-associated bacteria obtained from diverse environments. Our screening process identified 49 bacterial species in two lichens from the Himalayas: 17 species of Actinobacteria, 19 species of Firmicutes, and 13 species of Proteobacteria. We discovered five types of strong antimicrobial agent-producing bacteria. Although some strains exhibited weak antimicrobial activity, NP088, NP131, NP132, NP134, and NP160 exhibited strong antimicrobial activity against all multidrug-resistant strains. Polyketide synthase (PKS) fingerprinting revealed results for 69 of 148 strains; these had similar genes, such as fatty acid-related PKS, adenylation domain genes, PfaA, and PksD. Although the association between antimicrobial activity and the PKS fingerprinting results is poorly resolved, NP160 had six types of PKS fingerprinting genes, as well as strong antimicrobial activity. Therefore, we sequenced the draft genome of strain NP160, and predicted its secondary metabolism using antiSMASH version 4.2. NP160 had 46 clusters and was predicted to produce similar secondary metabolites with similarities of 5-100%. Although NP160 had 100% similarity with the alkylresorcinol biosynthetic gene cluster, our results showed low similarity with existing members of this biosynthetic gene cluster, and most have not yet been revealed. In conclusion, we expect that lichen-associated bacteria from the Himalayas can produce new secondary metabolites, and we found several secondary metabolite-related biosynthetic gene clusters to support this hypothesis.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.9 no.4
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• pp.725-733
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• 2019

The study aimed to effect of leisure support and leisure constraints on life satisfaction for extreme sports participants. A total of 179 adults from Seoul, In-chon, Gyeonggi, and Chungcheng-do were recruited. I conducted frequency, reliability, confirmatory factor, correction, and structure equaling modeling analyses using PASW Statistics 18.0 and AMOS 18.0. The results were as follows: (1) leisure attitude of leisure activity participants had a positive influence on leisure satisfaction; (2) leisure attitude of leisure activity participants had no influence on psychology happiness; (3) leisure satisfaction of leisure activity participants had no influence on psychology happiness. Leisure satisfaction has no mediating effect between leisure attitude and psychological well-being. However, leisure attitude has a positive influence on leisure satisfaction, so we need to develop infrastructure which it continue participate in leisure activity.

• Korean Journal of Chemical Engineering
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• v.35 no.11
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• pp.2220-2231
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• 2018

Lipase from Candida rugosa was immobilized on $MgO{\cdot}SiO_2$ hybrid grafted with amine, thiol, cyano, phenyl, epoxy and carbonyl groups. The products were analyzed using Fourier transform infrared spectroscopy, nuclear magnetic resonance, low-temperature $N_2$ sorption and elemental analysis. Additionally, the degree of coverage of the oxide material surface with different functional groups and the number of surface functional groups were estimated. The Bradford method was used to determine the quantity of immobilized enzyme. The largest quantity of enzyme (25-28 mg/g) was immobilized on the hybrid functionalized with amine and carbonyl groups. On the basis of hydrolysis reaction of p-nitrophenyl palmitate to p-nitrophenol, it was determined how the catalytic activity of the obtained biocatalysts is affected by pH, temperature, storage time, and repeated reaction cycles. The best results for catalytic activity were obtained for the lipase immobilized on $MgO{\cdot}SiO_2$ hybrids with amine and carbonyl groups. The biocatalytic system demonstrated activity above 40% in the pH range 4-10 and in the temperature range $30-70^{\circ}C$. Lipase immobilized on the $MgO{\cdot}SiO_2$ systems with amine and epoxy groups retains, respectively, around 80% and 60% of its initial activity after 30 days of storage, and approximately 60-70% after 10 reaction cycles.

• International conference on construction engineering and project management
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• 2013.01a
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• pp.359-366
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• 2013

Although many research efforts have been conducted to address the effect of crew members' work skills (e.g., technical and planning skills) on work performance (e.g., work duration and quality) in construction projects, the relationship between skill and performance has generated a great deal of controversy in the field of management (Inkpen and Crossan 1995). This controversy can lead to under- or over-estimations of the overall project schedule, and can make it difficult for project managers to implement appropriate managerial policies for enhancing project performance. To address this issue, the following aspects need to be considered: (a) work performances are determined not only by individual-level work skill but also by the group-level work skill affected by work team members, each member's role, and any working behavior pattern; (b) work planning has significant effects on to what extent work skill enhances performance; and (c) different types of activities in construction require different types of work, skill, and team composition. This research, therefore, develops a system dynamics (SD) model to analyze the effects of both individual-and group-level (i.e., multi-level) skill on performances by utilizing the advantages of SD in capturing a feedback process and state changes, especially in human factors (e.g., attitude, ability, and behavior). The model incorporates: (a) a multi-level skill evolution and relevant behavior development mechanism within a work group; (b) the interaction among work planning, a crew's skill-learning, skill manifestation, and performances; and (c) the different work characteristics of each activity. This model can be utilized to implement appropriate work planning (e.g., work scope and work schedule) and crew management policies (e.g., work team composition and decision of each worker's role) with an awareness of crew's skill and work performance. Understanding the different characteristics of each activity can also support project managers in applying strategic work planning and crew management for a corresponding activity, which may enhance each activity's performance, as well as the overall project performance.

• Food Science and Preservation
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• v.30 no.3
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• pp.538-545
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• 2023

This study aimed to assess the in vitro safety of a probiotics mixture (Lactobacillus acidophilus PBS066, Lactiplantibacillus plantarum PBS067, and Limosilactobacillus reuteri PBS072), along with its inhibitory effect on carbohydrate digestion. All three strains met the antibiotic resistance profile of the European Food Safety Authority (EFSA) guidelines. None of the strains exhibited hemolytic activity or cytotoxicity against Caco-2 cells. Strains PBS067 and PBS072 inhibited α-amylase activity, whereas all three strains suppressed α-glucosidase activity, indicating that the mixture might limit carbohydrate digestion in the gastrointestinal tract. These findings support the safety of this probiotics mixture and its potential to modulate carbohydrate metabolism in the gut.

• 대한공업교육학회지
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• v.39 no.2
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• pp.19-36
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• 2014

The purposes of this study are to grasp industry vocational subject student-teachers' instruction area, compare cognitive level of cooperating teacher and student-teachers for the importance of instruction area and secure base data required to develop educational practical area of professional teachers in specialized high school. To achieve this, instruction area of instruction teacher in charge of industry vocational subject pre-teacher education was developed by document consideration and expert verification and differences of importance cognition for the area was compared between educational practice insturction teacher and student-teacher. The results are as the following. First, for the instruction areas that educational practice instruction teachers should teach student-teacher, there are 7 categories, 17 mid-fields and 85 subsections. Especially expert group suggested an opinion that areas of teacher's values and personality formation should be added to pre-teachers. And, they judged that category of school business showed low validity for educational practice instruction teacher's instruction area. Second, educational practice instruction teacher importantly cognized 'class activity', 'student instruction and class management' and 'development of desirable view of education attitude'. On the other hand, they cognized 'development and management of curriculum', 'support on educational activity', 'industrial-educational cooperation and tie with local community' and 'specialty improvement' less importantly. Student-teachers cognized 'class activity', 'student instruction and class management', 'specialty improvement', 'development of desirable view of education attitude' importantly. They cognized 'development and management of curriculum', 'support on educational activity' and 'industrial-educational cooperation and tie with local community' relatively less importantly. Third, both educational practice instruction teachers and student-teachers importantly cognized 'class activity', 'student instruction and class management' and 'development of desirable view of education attitude'. However, student-teachers importantly cognized, but educational practice instruction teachers didn't importantly cognized 'specialty improvement'. Both two group cognized 'development and management of curriculum', 'support on educational activity' and 'industrial-educational cooperation and tie with local community' less importantly.

• Journal of Convergence for Information Technology
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• v.9 no.11
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• pp.62-70
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• 2019

This study is a descriptive correlation study that analyzes the correlation between health-related lifestyle and quality of life characteristics of single household. Variables were selected 1,220 surveys of single household from the Korea Health Panel 2015. The average age of single-person households in Korea was 68.19, with women accounting for 71.3% of the single-person households. One household due to each private sector accounted for 64.8%, while 42.3% responded to their subjective health status as "ordinary." Smokers accounted for 31.7% and drinkers 34.7%, with 55.3%t of the low-activity group making up the largest amount of physical activity. The quality of life score was $13.31{\pm}1.828$. There was a positive correlation between smoking, drinking, physical activity and quality of life. Based on this data, progress of physical activity improvement program in support of the diversity and social relations are needed, and individual psychological and emotional support of single household needs to be developed.

• Journal of agricultural medicine and community health
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• v.24 no.1
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• pp.115-129
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• 1999

To find the influence of family support degree on the depression of the elderly in a rural area, a questionnaire survey was made toward 163 persons who were more than 65 years old and living in a township at Chollanamdo province from January 1st to February 20th, 1998. The major findings are as follows : 1. By simple analysis significantly associated variables with depression score were residence, adequacy of pocket money, health consciousness, drinking alcohol, smoking, score of activity of daily living(ADL), score of instrumental activities of daily living(IADL), and degree of family support among female respondents(p<0.05). 2. To find the influence of family support on the depression score excluding other associated variables, multiple regression analysis was made and it was found that family support was associated significantly with affective, somatic, psychomotor and psychological domain of depression score among male, and somatic, psychomotor and psychological domain among female(p<0.05). The above finding suggest that family support degree is an important factor to be associated with the depression of the elderly in the rural area. So to deal with the depression of rural elderly, how to make close relation among family members must be considered.