• Korean Journal of Veterinary Research
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• v.48 no.3
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• pp.267-274
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• 2008

This study was to evaluate the efficacy of single dose Mycoplasma hyopneumoniae (M. hyo)-vaccination in the swine farms which had different serological patterns of porcine reproductive and respiratory syndrome virus (PRRSV) and porcine circovirus type 2 (PCV2). A minimum of 240 pigs from each farm was applied, allocating M. hyo vaccinated and control groups. The PRRSV and PCV2 infections were analyzed by serological method (commercial ELISA kit). After administrating pigs a single dose of M. hyo vaccine or control saline at 3 weeks of age, serum antibodies to M. hyo, PRRSV and PCV2 were monitored at 4, 10, 16 and 22 weeks of age. Mortality, weight changes, feed conversion ratio (FCR) and lung score were also evaluated. A single-dose vaccination of M. hyo bacterin was efficacious to reduce mycoplasmal lung lesions and induce good humoral immune response. However, FCR was improved only in one of the three farms where showed seronegative status to both PRRSV and PCV2 in the period from 4 to 16 weeks of age. These results might imply that M. hyo vaccine alone could not overcome the PRRSV and PCV2 infection-associated wasting in the field condition. Therefore, the control of PRRSV and PCV2 should be considered to obtain the better effects of M. hyo vaccination.

• Journal of Digital Convergence
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• v.15 no.6
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• pp.415-423
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• 2017

This study explored research trends by investigating articles published in the Journal of Korean Society of Fashion Design from 2001 through 2015. English key words and abstracts were analyzed using text mining and topic modeling techniques. The findings are as followings. By the text mining technique, 183 core terms, appeared more than 30 times, were derived from 7137 words used in total 338 articles' key words and abstracts. 'Fashion' and 'design' showed the highest frequency rate. After that, the well-received topic modeling technique, LDA, was applied to the collected data sets. Several distinct sub-research domains strongly tied with the previous fashion design field, except for topics such as fashion brand marketing and digital technology, were extracted. It was observed that there are the growing and declining trends in the research topics. Based on findings, implication, limitation, and future research questions were presented.

• JSTS:Journal of Semiconductor Technology and Science
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• v.7 no.1
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• pp.51-55
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• 2007

This paper investigates the subthreshold behavior of Fin Field Effect Transistor (FinFET). The FinFET is considered to be an alternate MOSFET structure for the deep sub-micron regime, having excellent device characteristics. As the channel length decreases, the study of subthreshold behavior of the device becomes critically important for successful design and implementation of digital circuits. An accurate analysis of subthreshold behavior of FinFET was done by simulating the device in a 3D process and device simulator, Taurus. The subthreshold behavior of FinFET, was measured using a parameter called S-factor which was obtained from the $In(I_{DS})\;-\;V_{GS}$ characteristics. The value of S-factor of devices of various fin dimensions with channel length $L_g$ in the range of 20 nm - 50 nm and with the fin width $T_{fin}$ in the range of 10 nm - 40 nm was calculated. It was observed that for devices with longer channel lengths, the value of S-factor was close to the ideal value of 60 m V/dec. The S-factor increases exponentially for channel lengths, $L_g\;<\;1.5\;T_{fin}$. Further, for a constant $L_g$, the S factor was observed to increase with $T_{fin}$. An empirical relationship between S, $L_g$ and $T_{fin}$ was developed based on the simulation results, which could be used as a rule of thumb for determining the S-factor of devices.

• Korean Journal of Agricultural Science
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• v.16 no.1
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• pp.36-43
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• 1989

Out of 826 isolates of Streptomyces isolated from different soils, their distribution and antibiotic productivity were investigated. Distribution of the organism in the soil was affected by the soil conditions and plants. The highest isolation frequency was occurred from Quercus forest, Robinia forest and grass field, while soils from orchards and cultivating fields showed low density of Streptomyces. More than 49% of the isolates showed antibacterial activity against Bacillus subtilis, Erwinia carotovora subsp. carotovora and Xantomonas campestris pv. oryzae and about 40% of the isolates showed antiyeasty activity against Saccharomyces cerevisiae but only a few isolates showed antibiotic activity against E. coli and Pseudomonas solanacearum. Forty isolates of the Streptomyces showed strong antifungal activity against Pyricularia oryzae. Rate of isolation of Streptomyces was the highest on starch agar among the eight media tested. Antibiotic productivity of the isolates was the highest on potato sucrose agar medium among the 5 media tested.

• Journal of dental hygiene science
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• v.20 no.2
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• pp.107-117
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• 2020

Background: In this study, we tried to comprehensively explore clinical dental hygienist's experience of a prevention-based incremental oral health care program, which was pilot-operated by dental clinics, define prevention-based incremental oral health care as experienced in the field, and identify factors to be considered. Methods: This study conducted a focus group interview with five dental hygienists who participated in an ongoing oral management pilot project in 2016. The interview was conducted by a researcher, and the co-research team attended as progress assistants and recorded characteristics of the participants, main dictations, and non-verbal characteristics. All interviews were recorded and underwent thematic analysis to examine the questions of the study as the main axis. Results: As a result of the study, 65 meaningful statements were extracted by code, integrated into 24 sub-categories, and structured into 11 categories. Finally, four keywords were drawn: characteristics, facilitating factors, conflicting factors, and improvement measures for prevention-based incremental oral health care. Regarding prevention-based incremental oral health care in dental clinics, dental hygienists were highly aware of the physical and mental burdens of personalized treatment and education for each individual. They were responsible for the patient and for facilitating changes in the behavior of the client, leading to professional satisfaction. The dental team's cooperation and supportive attitude were found essential to continue oral health care in the dental clinic. Conclusion: Through dental team-based treatment philosophy sharing and collaboration, it is possible to provide prevention-based incremental oral health care in dental clinics. In future, it is necessary to develop a system for establishing a sustainable preventative management system for public health promotion.

• Journal of Korean Elementary Science Education
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• v.33 no.2
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• pp.401-414
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• 2014

The purpose of this study is to investigate the elementary preservice teachers' conceptions about 'plastics' focusing on non-polar property from a National University of Education. For the study, the views about plastics, relative shapes of a water droplet on plastic or glass material, and relative shapes of water surface in the plastic or glass measuring cylinder were surveyed from the preservice teachers. And the responses were analyzed based on the patterns. The results from the study are as follows: First, most preservice teachers were well aware of the plastic products which are used in daily life. Second, the responses concerning the reason why plastics can be used commonly were divided into 2 categories with 14 sub-level groups. However relatively few preservice teachers mentioned regarding 'chemical stability' and 'conductivity', which are associated with the plastics' non-polar property. Third, it was found that 50 participants (30.1%) had 'Scientific conception (Sc)', 38 (22.9%) had 'Partial-scientific conception (Ps)', 66 (39.8%) had 'Misconception (Mc)', and 12 (7.2%) had 'No conception (Nc)' on the subject of the relative shapes of a water droplet. Fourth, the distribution patterns and the ratio of the preservice teachers' conception on the survey question 3 concerning the relative shapes of water surface were quite similar to those of the survey question 2. So it was concluded that overall understanding level of the preservice teachers was pretty low on the subjects of the relative polarities of the plastic, glass, and water as well as their interactions. Fifth, the distribution percentile of 'Sc'/'Ps'/'Mc'/'Nc' was not related with the gender but highly correlated with preservice teachers' academic field and their science subjects taken in high school. Based on the results from the study, some educational guidelines were suggested.

• Journal of Environmental Science International
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• v.22 no.9
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• pp.1187-1197
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• 2013

The result of a small electrostatic precipitator which is in order to decrease indoor air pollution for optimal efficiency was shown as follows. Although the closer distance between the discharge electrode and dust collecting electrode shows the better throughput efficiency by forming strong electrostatic Field, it does not have profound impact in case of optimal dust collecting area. G.P(gas passage) which is the distance from dust collecting electrode to dust collecting electrode is a crucial factor to decide dust collecting efficiency. The narrower distance of G.P shows the better throughput efficiency whereas it decreases when the distance is too narrow since sparks ensue by increasing the capacity of electrostatic charging system 5 mm regards as optimal efficiency in this experiment. Although the higher voltage shows the higher dust collecting efficiency overall, the experiment was not able to keep performing since the sparks which decrease dust collecting efficiency ensue over 40 kV. The efficient and safe voltage state is considered 3.6 kV in this experiment. The most crucial factor for dust collecting efficiency of an electrostatic precipitator which is in order to decrease indoor air pollution is applied voltage. In addition, optimal raw gas flow rate(2.4 m/sec) is more important factor than the excessive increase of dust collecting area.

• The Journal of Korean Academic Society of Nursing Education
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• v.26 no.1
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• pp.25-35
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• 2020

Purpose: The purpose of this study was to investigate the effects of lessons based on flipped on nursing students' critical thinking disposition, academic achievement, and academic self-efficacy. Methods: The study design was a mixed methods paradigm. Participants were 82 nursing students (experimental group=41, control group=41) for the quantitative study, and nine nursing students for the qualitative study. A flipped learning lesson and lecture were provided in a class titled Critical Thinking and Nursing Processes to compare the effects of the flipped learning lesson. Quantitative data were analyzed with a chi-square test and an independent t-test. Qualitative data were analyzed by means of content analysis. Results: The critical thinking disposition (t=-5.90, p=.004) of the experimental group with flipped learning increased significantly, but their academic achievement (t=0.38, p=.078) and academic self-efficacy (t=-0.24, p=.053) did not show any significant change. From the content analysis after the flipped learning lesson, four categories and 13 sub-categories were derived. Conclusion: The results of this study showed that flipped learning is an effective teaching-learning method for improving nursing students' critical thinking disposition. Therefore, it will be necessary to consider teaching-learning management strategies for applying flipped learning in the nursing education field.

• Publications of The Korean Astronomical Society
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• v.26 no.3
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• pp.89-101
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• 2011

The International Olympiad on Astronomy and Astrophysics (IOAA) initiated by the Thailand Astronomical Society in 2007 is an annual competition for high school students. One of its aim is to enhance the development of international exchange in the field of school education in astronomy and astrophysics. This paper first provides the overview of the IOAA in terms of key regulations based on its statutes, history and current status. Secondly, the published syllabus of the IOAA is used for content analysis according to subject areas regarding the exam questions of the IOAA in theoretical, observational and data analysis parts from 2007 to 2010. Also, a scientific inquiry framework is applied to the same questions for assessment based on scientific inquiry in the cognitive aspect with two sub-classes of scientific knowledge and scientific reasoning. Among a dozen astronomy subject areas listed on the syllabus, the theoretical part of the IOAA makes more frequent use of the Sun, the solar system, properties of stars, and concept of time. In content knowledge, a factor of scientific knowledge, the IOAA questions, especially in the theoretical part have a lesser degree in difficulty than the IAO (International Astronomy Olympiad) exam questions for the same period whose degree in difficulty is comparable to college level. With regard to scientific reasoning, the IOAA questions tend to involve convergent rather than divergent thinking. Lastly, in light of these findings, discussions are given on the outcome of Korean participation in the previous IOAAs and ways to help better in preparing Korean students for future astronomy Olympiads.

• The Korean Journal of Elementary Counseling
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• v.5 no.1
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• pp.185-204
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• 2006

The object of this study is to inspect how much influence the play-based assertive training program has on the self-expression and learning attitude of elementary students. To perform this study, I set up two subjects of research. First, does the play-based assertive training program have influence on the self-expression improvement of elementary students? Second, does the play-based assertive training program have influence on the attitude of elementary students? I established 28 students in the third grade of K elementary school in Gongju City as experiment group for this research. In experiment group, 1 peformed play-based assertive training program in the class of discretion and extra-curricula activity twice a week and maintained the program for 6 weeks. By the standard of 12 times of performances, I put pre-test and post-test into operation. The major consequences revealed through above processes are followed: First, as the consequence of analyses of differences between pre-test and post-test about self-expression of experiment group adapted by play-using assertion training program, the level of self-expression was advanced meaningfully. Second, as the consequences of analyses of differences between pre-test and post-test about learning-attitude of experiment group adapted by play-based assertive training program, the level of learning-attitude was advanced meaningfully. Among 8 sub-fields of learning attitude, the field of superiority, accomplishment motives, concentration, self-study show statistically meaningful difference s respectively. The conclusion drawn from above consequences is that the play-based assertive training program is very effective in developing students' self-expression and attitude for learning.