• Advances in nano research
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• v.15 no.4
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• pp.355-366
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• 2023

Biological corrosion, a crucial aspect of metal degradation, has received limited attention despite its significance. It involves the deterioration of metals due to corrosion processes influenced by living organisms, including bacteria. Soil represents a substantial threat to pipeline corrosion as it contains chemical and microbial factors that cause severe damage to water, oil, and gas transmission projects. To combat fouling and corrosion, corrosion inhibitors are commonly used; however, their production often involves expensive and hazardous chemicals. Consequently, researchers are exploring natural and eco-friendly alternatives, specifically nano-sized products, as potent corrosion inhibitors. This study aims to environmentally synthesize silver nanoparticles using an extract from Lagoecia cuminoides L and evaluate their effectiveness in preventing biological corrosion of buried pipes in soil. The optimal experimental conditions were determined as follows: a volume of 4 ml for the extract, a volume of 4 ml for silver nitrate (AgNO3), pH 9, a duration of 60 minutes, and a temperature of 60 degrees Celsius. Analysis using transmission electron microscopy confirmed the formation of nanoparticles with an average size of approximately 28 nm, while X-ray diffraction patterns exhibited suitable peak intensities. By employing the Scherer equation, the average particle size was estimated to be around 30 nm. Furthermore, antibacterial studies revealed the potent antibacterial activity of the synthesized silver nanoparticles against both aerobic and anaerobic bacteria. This property effectively mitigates the biological corrosion caused by bacteria in steel pipes buried in soil.

• Journal of The Korean Association For Science Education
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• v.32 no.5
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• pp.805-822
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• 2012

The purpose of this study was to explore the patterns of group model development about blood flow in the heart and reasoning process by small group interaction. The subjects were 14, 8th graders in a Science Gifted Center. The group discussion was made possible by using triggering questions that can be answered based on experiences of hands-on activities such as a siphon pump analogy model activity and a dissection of pigs' hearts. Despite participating in same activities, the groups showed different model development patterns: unchanged, persuasive, and elaborated. Due to the critical revising, the group's explanatory model was elaborated and developed in the added and elaborated pattern. As critical revising is a core element of the developing model, it is important to promote a group interaction so that students become critical and receptive. The pedagogical analogy model and conflict situation enabled students to present elaborated reasoning. The Inquiry activity with the pedagogical analogy model promote students' spontaneous reasoning in relation to direct experience. Therefore offering a pedagogical analogy model will help students evaluate, revise and develop their models of concerned phenomena in science classroom. Conflict situation by rebuttal enable students to justify more solid and elaborate a model close to the target model. Therefore, teachers need to facilitate a group atmosphere for spontaneous conflict situation.

• The Journal of Korean Association of Computer Education
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• v.7 no.6
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• pp.95-105
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• 2004

It is important to understand how pre-service teachers perceive e-learning because their prior-experience with e-learning will have a great impact on their teaching after the graduation. Pre-service teachers (401 students) with cyber learning experience, which is a form of e-learning, were selected in 2004 in May and June. Survey was conducted regarding the instructional experience (working hours, tasks and evaluation, satisfaction about cyber learning and its academic achievement, difficulties and suggestions) and instructional methods (instructional activities, frequencies of interaction, strategies of interaction, collaborative activities, behaviors in the group instructional activities for knowledge development). The results are pre-service teachers tent to spend similar v slightly less working hours for cyber learning, similar or slightly less satisfaction level for the instruction and the academic achievement. It was interesting that female students were more negative than males students, considering female students have been more active in online discussion traditionally. Logical presentation of contents and instructional strategies for the cyber learning were the most wanting suggestions. E-mails and BBS for reference materials were the two most used functions in the online learning. The amount and types of tasks were satisfactory. Students did not interact freely during the group activities, they reported they did not learn much through the group activity. During the group work, they consider they do their roles with responsibility while they have slightly negative responses toward other members' contribution in the group activity. Off line meeting is strongly suggested.

• Journal of Distribution Science
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• v.14 no.6
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• pp.107-118
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• 2016

Purpose - Over 90% of Domestic logistics industry is small enterprise and they are experiencing growth stagnation due to price-based competition structure rather than constructing logistics service of high added value. In order to get over this situation and pursue the development of logistics industry, strengthening its competitiveness, through inter-enterprise cooperative network build-up, would be a key alternative. Therefore, in this study, an index for measuring inter-enterprise cooperation level of Joint logistics business will be developed as a typical collaborative business model in logistics industry. Moreover, a strengthening competitiveness method suggests a developmental step and a key management index to mature in logistics industry. Research Design, Data, Methodology - This study is an index development research for measuring inter-enterprise cooperation level of logistics industry. Such a level was measured by performing a survey by targeting enterprises that participated in Joint logistics business. The targeting enterprises are typical cooperative models in logistics industry. Measurement items were developed which were based on the presented items in existing research. Question items were composed of selection type questions as answering Yes/No. They measures implementation status of corporate activity and detailed activity items measuring qualitative level. Total samples were based on 116 enterprise samples including 90 logistics enterprises and 26 shippers. In addition, by evaluating the importance for Joint logistics business recognition with personnel working level, the weight of measuring variable was extracted. This study has built an assessment tools (LPCI) on Joint logistics business cooperation level in a situation where there are no previous studies on joint logistics business, this study is meaningful for other studies. Results - As a result of analyzing LPCI presented in this study, the score of logistics enterprise was represented as 59.9 points based on full score of 100 points and that of shippers as 47.2 points and cooperation level among enterprises participated in Joint logistics business was revealed to be very low. In particular, as a result of measuring the importance between logistics enterprise and shippers, the difference by each measurement standard was represented among those enterprises. This difference is considered to be a key factor that cooperative operational conformity between logistics enterprises and shippers is represented to be low. Conclusions - As most joint logistics business, being promoted at present, is sharing facility and information with joint logistics business, it is hard to find such a joint logistics business in reality based on cooperative business model in main cooperation agents. Therefore, competitiveness of logistics industry could be strengthened by promoting joint logistics business based on their mutual cooperation among enterprises. In other words, it is to secure sustainable competitiveness of joint logistics business together with creation of new market by inter-enterprise cooperation based on integration of basic logistics business.

• Journal of Ginseng Research
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• v.48 no.5
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• pp.454-463
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• 2024

Background: Panax quinquefolius L, widely recognized for its valuable contributions to medicine, has aroused considerable attention globally. Different from the extensive research has been dedicated to the root of P. quinquefolius, its berry has received relatively scant focus. Given its promising medicinal properties, this study was focused on the structural characterizations and anti-inflammatory potential of acidic polysaccharides from the P. quinquefolius berry. Materials and methods: P. quinquefolius berry was extracted with hot water, precipitated by alcohol, separated by DEAE-52-cellulose column to give a series of fractions. One of these fractions was further purified via Sephadex G-200 column to give three fractions. Then, the main fraction named as AGBP-A3 was characterized by methylation analysis, NMR spectroscopy, etc. Its anti-inflammatory activity was assessed by RAW 264.7 cell model, zebrafish model and molecular docking. Results: The main chain comprised of α-L-Rhap, α-D-GalAp and β-D-Galp, while the branch consisted mainly of α-L-Araf, β-D-Glcp, α-D-GalAp, β-D-Galp. The RAW264.7 cell assay results showed that the inhibition rates against IL-6 and IL-1β secretion at the concentration of 625 ng/mL were 24.83 %, 11.84 %, while the inhibition rate against IL-10 secretion was 70.17 % at the concentration of 312 ng/mL. In the zebrafish assay, the migrating neutrophils were significantly reduced in number, and their migration to inflammatory tissues was inhibited. Molecular docking predictions correlated well with the results of the anti-inflammatory assay. Conclusion: The present study demonstrated the structure of acidic polysaccharides of P. quinquefolius berry and their effect on inflammation, providing a reference for screening anti-inflammatory drugs.

• Journal of The Korean Association For Science Education
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• v.40 no.2
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• pp.113-126
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• 2020

In this study, we investigated science teacher's guidance of teaching practice in the perspective of the CHAT. Two science teachers working for schools affiliated with a college of education in Seoul took part in this study. Visiting the entire teaching practice, we observed the processes of guidance and the lessons and collected related materials. Semi-structured interviews were also conducted before, during and after teaching practice. All the data were analyzed by using the constant comparative method. The analyses of the results revealed that student guidance during the lessons was also important. And the curriculum orientation needed to be carried out before teaching practice. The division of labor with pre-service teachers relieved teachers of work burden. Teachers failed to guide assessment of students due to influences of community element such as students who were sensitive to grades. In both cases, teaching practice were so collaborative that those were valuable not only for pre-service teachers but also for teachers and students. Two teachers' activity system showed contradictions due to the lack of specific manuals for guidance and the lack of understanding of pre-service teachers. These contradictions brought about difficulties in their guidance, which in turn led to the difficulties experienced by pre-service teachers during teaching practice. They attempted to resolve contradictions in alternative ways and required standardized manuals for guidance, environments in which teachers could collaborate, and close connections with a college of education. Based on the results, we suggest some ways to improve teaching practice.

• Journal of the Korean Society of Marine Environment & Safety
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• v.25 no.6
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• pp.743-748
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• 2019

This study suggested a process of redesigning and implementing problem based learning to enhance students' active and collaborative learning activities and learning outcomes. The results of this study are as follows. First, the ef ect of class participation, academic self-regulated learning, and academic self-efficacy were examined. As a result, first, the average of learning activity, class extension, and participation in class was high in the difference between before and after class. Second, the post average scores of all the factors except the 'evaluation' were higher than before. Third, academic self-efficacy showed a significant difference only in 'task preference'. Finally, students' satisfaction with the class was also high. The professor was also able to grasp the characteristics of individual students by designing and operating the classes using PBL, and it was confirmed that the interaction with students increased. Based on the results of this study, we discussed the limitations and educational implications of the problem based learning class and propose successful problem based learning design and operation of the classroom.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.13 no.2
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• pp.59-73
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• 2002

Libraries, not only research libraries but also public libraries, have been fundamentally affected by the immense spread of the Internet and the World Wide Web. Many public libraries have their Web pages, through which they are providing their new and conventional services. There are also web sites which provide library-like services. This paper shows an experimental project named Internet Public Library Asia, which provides information in multiple languages of information resources published in Chinese, Japanese and Korean languages. This paper firstly overviews how traditional public libraries have been affected by the Internet. Then, it describes a few aspects from the viewpoint of crucial library function on the Internet and also from the viewpoint of Asian resources and users. This paper secondly proposes a model to serve information about valuable resources published in multiple Asian languages, and then shows the metadata schema and a few software tools developed for IPL-Asia The name of IPL is borrowed from Internet Public Library based at University of Michigan, since it is, in part, a collaborative activity with the IPL in Michigan. The metadata schema is defined based both on Dublin Core and IEEE LOM and adapted for parallel description in the four languages, i. e. , Chinese, Japanese, Korean and English. The software tools provide functions to support collaboration among people engaged in development of metadata database and metadata editing. These tools have been developed based on the XML technologies.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.8 no.2
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• pp.132-146
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• 2001

Purpose: This study was to analyze the trends and content of all the research (171 research papers) published in the Journal of Fundamentals of Nursing from 1994, when it began to 2000 using an objective tool developed by the researches, and to identify the direction for the future research in Fundamentals of Nursing. Method: Research published in the Journal of Fundamentals of Nursing from 1994 were reviewed. Result: Most of research (94.2%) was non-degree based and funded research was very limited. The average number of researchers per research study was 2.2 and collaborative research has been gradually increasing. The total number of key words was 331 and the average was 2.6 per research. The major key words were not different from other nursing departments and included home care nursing (10 times), health promotion (8 times), self-care (7 times). self-efficacy (7 times), and homo-dialysis (6 times). Eighty seven percent of the research was quantitative research. and there were very few qualitative studies. Considering theory level, it was found that 40% were factor related research For study design, non-experimental studies were most frequent (66%), and the rate, especially of surveys, has remarkably decreased. Selection of subjects by convenience sampling, was most frequent and there were very few studies that provided the rationale for the calculation of sample size. The major subjects of study were patients (44.8%) with various diagnoses. The subjects usually gave oral consent to take part in that study. Giving information (46.9%) and exercise (26.5%) were common nursing interventions, and physiological indices (16.5%). vital signs (10.3%), physical functioning (8.2%), level of knowledge/skill (7.2%) and level of activity (6.2%) were frequently measured as outcome. Variables questionnaires were the major approach used to collect data, and 57.8% of the research provided the Cronbach alpha to guarantee internal consistency of study instruments. Data were analyzed with computerized statistical packages using, ANOVA (42.0%), T test(39.5%), and chi-square test. For the last seven years, nursing research in Fundamentals of Nursing has gradually improved in both quantify and quality. Conclusion: It was difficult to find any uniqueness or difference compared to other departments of nursing. In fact, because the history of the Journal of Fundamentals of Nursing is rather short, we can expect that there will be further improvement in qualify and content in the future.

• The Journal of the Korea Contents Association
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• v.15 no.11
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• pp.202-214
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• 2015

This study aims to develop and apply communication and relationship enrichment programs for married multicultural couples and verify its effects. This preliminary program was developed based on results from reviews of existing intervention programs, participants' interview for their needs and professionals' feedback on program. The program includes 11 sessions(once a week; 2 hours per session) focusing on communication strategies and related activities using marital counseling. Four multicultural couples participated in the intervention program. Qualitative data was collected during the program, including voice recording files, activity sheets, and filed notes conducted by researchers. Based on the results from the data analysis, we could find the intervention program had an positive effect on the communication between multicultural couples. Specifically, the intervention program could (1) enhanced intimacy in the couples, (2) started conversation and improved communication patterns between the couples. And also (3) modes of communication were changed to more collaborative communication through this program. The marital communication program developed in this study is significant in that it played a catalytic role for marital conversation in multicultural couples and used professional counseling techniques and strategies in solving and managing marital conflict.