• Proceedings of the KIEE Conference
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• 2007.11b
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• pp.139-141
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• 2007

차단기, 단로기와 간은 개폐기는 투입 동작이 이루어질 때, 접점 간의 내전안과 양단간의 전안차 사이의 관계에 의하여 pre-strike 현상이 발생한다. 따라서, 개폐기가 투입되는 동안 발생하는 과도철상을 파악하기 위해서는 개폐기의 pre-strike 친상을 모델링하는 것이 중요하다. 본 논문에서는 개폐기의 pre-strike 현상을 EMTP로 모델링하고 이를 모델 계통에 적용하여 구현된 pre-strike 모델이 타당함을 보였다.

• Animal cells and systems
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• v.11 no.2
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• pp.129-134
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• 2007

The initiation of eukaryotic DNA replication requires assembly of the pre-replicative complex (Pre-RC) through the concerted action of Orc, Cdc6, Cdt1 and Mcm2-7 complex during G1 phase. The pre-RC assembly licenses individual replication origins for the initiation of DNA replication and sufficient number of the pre-RC is essential for proper progression of S phase. However, it is not well known how cells recognize the completion of the pre-RC assembly before G1-S transition. In order to understand the cellular responses to the defects in pre-RC assembly, we depleted the known components of pre-RC proteins using the small interference RNAs in HeLa cells. Although the defects of pre-RC assembly by the depletion of the pre-RC proteins such as Orc2, Cdt1, Mcm2 & Mcm10 did not elicit the activation of Chk1- or Chk2-dependent checkpoint pathways, these cells still showed significant decrease in the cellular level of Cdc25A proteins. These results suggests that a novel checkpoint pathway exist in HeLa cells, which is not dependent upon Chk1 or Chk2 proteins and play essential roles in the cellular responses to the defects in the pre-RC assembly. Also, among those four proteins tested in this study, the depletion of Mcm10 and Cdt1 proteins significantly increased the apoptotic cell death in HeLa cells, suggesting that these proteins not only play roles in the pre-RC assembly, but also are involved in the checkpoint responses to the defects in the pre-RC assembly.

• Food Science of Animal Resources
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• v.34 no.2
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• pp.158-165
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• 2014

The effects of replacing pork back fat with brewer's spent grain (BSG) pre-emulsion for physicochemical, textural properties, and sensory evaluations of reduced-fat chicken sausages are evaluated. Control was prepared with 15% pork back fat, and three reduced-fat chicken sausages were formulated with the replacement of 20, 25, and 30% pork back fat with BSG pre-emulsion. The pH level of reduced-fat sausages formulated with BSG pre-emulsion is lower than that of the control (p<0.05). The redness, yellowness, and apparent viscosity of reduced-fat chicken sausages increase proportionally with increasing BSG pre-emulsion (p<0.05). With increasing BSG pre-emulsion concentration, the fat contents and energy values are decreased in reduced-fat chicken sausages (p<0.05). The BSG pre-emulsion improves the hardness, gumminess, and chewiness of reduced-fat chicken sausages (p<0.05), and the reduction in fat and the addition of BSG pre-emulsion had no influence on the cohesiveness of the chicken sausage. And there is no significant difference in the overall acceptability among control, T1 (chicken sausage with 20% of BSG pre-emulsion, 10% of fat addition), and T2 (chicken sausage with 25% of BSG pre-emulsion, 5% of fat addition) (p>0.05). Therefore, our results indicate that BSG is effective dietary fiber source for manufacturing of reduced-fat meat product and suggest that 20-25% of BSG pre-emulsion is suitable for pork back fat in chicken sausages.

• Journal of Korean Elementary Science Education
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• v.31 no.1
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• pp.109-124
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• 2012

Developing pedagogical content knowledge (PCK) has been emphasized for teacher's professionalism and it should be done from systematic teacher training courses. In this study, we investigated changes of elementary pre-service teachers' PCK of science teaching and motivational strategies before and after a training course. For the analysis of pre-service teachers' PCK, their lesson plans, surveys, and interviews were collected. According to the results, in the beginning of the semester, pre-service teachers in the experimental group usually used didactic or combination of didactic and inquiry teaching strategies and a few pre-service teachers used inquiry or discovery teaching strategies when making lesson plans. However, at the end of the semester many pre-service teachers used inquiry teaching strategies in their lessons which included activities of asking students' prior knowledge, conducing experiments, finding conclusion, and comparing teachers' explanations with students' explanations. Regarding motivational strategies, in the beginning of the semester they focused using activities to create student's emotional interest in science lesson but at the end they used other strategies to create positive atmosphere for learning, capture intellectual interest in science, and connect science to students' everyday lives. The changes in pre-service teachers' PCK in the experimental group was meaningful because there was less change in pre-service teachers' PCK in the control group. This study implies the need for effective professional development programs for developing pre-service teachers' PCK.

• Journal of the Korean Society of Earth Science Education
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• v.15 no.2
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• pp.249-262
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• 2022

This study was conducted on the alternative concept of elementary school pre-service teachers to seasonal changes. From May 2021 to June 2022, it was conducted with 60 pre-primary teachers at P National University of Education. The conclusion of this study is as follows. First, pre-primary teachers explained the cause of seasonal changes, and out of 60 pre-primary teachers, only 22 (36%) had scientific concepts, and the remaining 38 (64%) students had alternative concepts. Second, in explaining how the inclination of the Earth's axis of rotation is related to seasonal changes, only 16 (27%) of the 60 pre-primary teachers had a scientific concept, and the remaining 44 (73%) had alternative concepts. Third, pre-primary teachers explained the relationship between the change in the solar altitude and the seasonal change. Among 60 pre-primary teachers, 12 (20%) had a scientific concept, and the remaining 48 (80%) had alternative concepts. Fourth, looking at the comprehensive types of alternative concepts for seasonal changes, the aS-bS-cS type, which is classified as a type that explains the causes of seasonal changes using scientific concepts as a whole, was 8(13%) out of 60 pre-primary teachers. and the remaining 52 (87%) had at least one alternative concept to explain seasonal changes.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.7
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• pp.325-331
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• 2019

This study investigated the effect of pre service teacher's empathic ability on teaching ethics, and child abuse report intention. The subjects were 168 pre-service teachers attending a university located in a micropolitan city. Questionnaires, which required self-reporting by pre service teacher, were used to investigate teacher's empathic ability, teaching ethics and child abuse report intention. The collected data were analyzed by frequency, percent, Pearson's correlation coefficient analysis and stepwise-regression analysis. From the major study findings, first, pre-service teacher's empathic ability was positively correlated with teaching ethics and child abuse report intention. Pre-service teacher's "take perspective", "imagine" of the cognitive empathic ability's subfactor was positively correlated with teaching ethics. Especially, empathic interest was positively correlated with teaching ethics. Cognitive empathy ability showed the highest relationship with ethics for early child. Emotional empathy showed the highest relationship with ethics in society. Second, the pre-service teacher's teaching ethics were influenced by taking perspective, imagining, and empathic attention. These results demonstrate the need to incorporate perspectives in the development of programs to promote pre - service early childhood teacher ethics and child abuse reporting.

• Microbiology and Biotechnology Letters
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• v.26 no.6
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• pp.566-568
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• 1998

Partial nucleotide sequence (nt 1-1842) of chloramphenicol resistance plasmid pKH7 has been reported previously and residual nucleotide sequence (nt 1843-4118) of pKH7 was determined and then the complete nucleotide sequence of pKH7 was obtained. pKH7 consists of 4118 bp and has three ORFs. Besides Rep and CAT proteins described in previous paper, Pre protein which mediates site-specific recombination in Staphylococcus aureus was found to be on pKH7. R $S_{A}$, a site-specific recombination site of Pre protein, and palA, a specific lagging-strand conversion signal, was also found in pKH7. Amino acid sequence of Pre protein of pKH7 was compared with those of other antibiotic resistant Staphylococcus aureus plasmids.s.

• The Korean Journal of Community Living Science
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• v.28 no.1
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• pp.115-130
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• 2017

This study was conducted to examine the relationship between pre-service early childhood teacher's motivations of choosing a teaching profession, educational belief, and self-directed learning readiness. The sample included 308 early childhood education major students, and the data were collected using the Modified Orientation to Teach Survey (MOTS), Teaching-belief type scale, and self-directed learning readiness scale. A statistical analysis included correlation analysis and stepwise multiple regression analysis. The results were as follows: 1) analysis of the relationship between pre-service early childhood teacher's motivations of choosing a teaching profession, educational belief, and self-directed learning readiness conveys that intellectual stimulation and self-directed learning had the strongest relationships while nature of work had the weakest. For educational belief and self-directed learning readiness, maturationism and interactionism showed significantly positive correlations while behaviorism displayed a negative correlation. Behaviorism had a significantly negative correlation with openness for challenge, a sub-factor of self-directed learning. 2) Analysis of the effect of pre-service early childhood teacher's motivations of choosing a teaching profession and educational belief on self-directed learning readiness indicates that pre-service early childhood teacher's motivations of choosing a teaching profession had a stronger effect on self-directed learning. These results suggest the following: successful performance as an early childhood teacher not only requires receiving institutionalized education but also self-directed learning while working as an early childhood teacher.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.11
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• pp.454-462
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• 2018

This study examines the influence of pre-service early childhood teacher's empathy and interpersonal competence on teacher efficacy. The subjects of this study include 358 pre-service early childhood teachers. The instruments used in this study were the emotional empathy scale, interpersonal competence questionnaire (ICQ) and the teacher efficacy scale. Collected data was analyzed using the SPSS program. In order to determine the general background of the pre-service teachers, the frequency and percentages were used. For examination of empathetic ability, interpersonal competence and teacher efficacy of pre-service early childhood teachers, a descriptive statistics analysis was conducted. In addition, in order to assess the relationship among empathetic ability, interpersonal competence and teacher efficacy of pre-service early childhood teachers, Pearson's correlation analysis was conducted. Lastly, for the examination of the effects and relative explanation of empathetic ability, interpersonal competence and teacher efficacy of pre-service early childhood teachers, multiple regression analysis was conducted. The results of this study were as follows: first, pre-service early childhood teachers were shown to have higher empathetic ability, interpersonal relationships and teacher efficacy rates than average. Second, there was a positive correlation among empathetic ability, interpersonal competence and teacher efficacy of pre-service early childhood teachers. Third, teacher efficacy of pre-service early childhood teachers was influenced by their empathetic ability and interpersonal competence. The results of this study suggest that teacher efficacy improvement programs for pre-service early childhood teachers should consider their empathetic ability. Also, study results emphasize the necessity of empathetic ability and interpersonal relationship improvement program for pre-service early childhood teachers.

• Journal of Microbiology and Biotechnology
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• v.1 no.4
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• pp.274-280
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• 1991

Effects of IPTG induction on cell growth and production of ${\beta}$-galactosidase-preS2 fusion protein (${\beta}$gal-preS2) were studied in a defined medium using a recombinant Escherichia coli JM109/pCMHB30. IPTG was added (0.2 mM) to induce the cloned-gene expression in the early-, mid-, and late-log growth phases. The most serious decreases in growth rate and plasmid stability were observed for the induction in the early-log growth phase. The expression level of ${\beta}$gal-preS2 attained by the induction in the mid-log phase was about 0.51 mg fusion protein/mg total cellular protein, which was 2- and 5-fold improvement over the levels obtained with the inductions in the early- and late-log phases. Formation of acidic byproducts including acetate and pyruvate showed different profiles during the fermentation period for each cases of induction; pyruvate was the major byproduct for the induction in the early-log phase while acetate production became more significant for the cases of inductions in the mid- and late-log phases.