• KOREAN POULTRY JOURNAL
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• v.56 no.2
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• pp.141-145
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• 2024

• The Mathematical Education
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• v.55 no.3
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• pp.317-334
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• 2016

Knowledge and data interpretation on statistical estimation was important to have statistical literacy that current curriculum was said not to satisfy. The author investigated mathematics teachers' MKT on statistical estimation concerning interpretation of confidence interval by using questionnaire and interview. SMK of teachers' confidence was limited to the area of textbooks to be difficult to interpret data of real life context. Most of teachers wrongly understood SMK of interpretation of confidence interval to have influence upon PCK making correction of students' wrong concept. SMK of samples and sampling distribution that were basic concept of reliability and confidence interval cognized representation of samples rather exactly not to understand importance and value of not only variability but also size of the sample exactly, and not to cognize appropriateness and needs of each stage from sampling to confidence interval estimation to have great difficulty at proper teaching of statistical estimation. PCK that had teaching method had problem of a lot of misconception. MKT of sample and sampling distribution that interpreted confidence interval had almost no relation with teachers' experience to require opportunity for development of teacher professionalism. Therefore, teachers were asked to estimate statistic and to get confidence interval and to understand concept of the sample and think much of not only relationship of each concept but also validity of estimated values, and to have knowledge enough to interpret data of real life contexts, and to think and discuss students' concepts. So, textbooks should introduce actual concepts at real life context to make use of exact orthography and to let teachers be reeducated for development of professionalism.

• Journal of Korean Medicine Rehabilitation
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• v.15 no.2
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• pp.55-65
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• 2005

Objectives : Mahwangkanghwal-tang(Mahuangqianghuo-tang;MKT) is a prescription that treat clinically arthritis. The purpose of this study is to investigate effects of MKT extract on the adjuvant arthritis in pathological rats induced by Freund's complete adjvant($0.2m{\ell}/kg$). Methods : Experimental groups were divided into 4 groups ; Normal group were administered DDW $1.0m{\ell}$ to normal rats for 14 days, Control group were administered DDW $1.0m{\ell}$ to arthritic rats for 14 days, Sample A group were administered MKT $300m{\ell}/kg$ $1.0m{\ell}$ to arthritic rats for 14 days, Sample B group were administered MKT $500m{\ell}/kg$ $1.0m{\ell}$ to arthritic rats for 14 days. The present author observed body weight, inhibitory effect of edema, analgesic effects by hot plate, WBC, RBC, hemoglobin, hematocrit, platelet, total serum protein level and total serum cholesterol level. Results : 1. All sample group were increased body weight compared with control group, sample B group were significantly increased body weighty compared with control group. 2. All sample group significantly inhibited the rated of paw edema compared with control group. 3. All sample group significantly prolongated the escaping time compared with control group, sample B group significantly prolongated the paw licking time compared with control group. 4. All sample group were significantly decreased WBC compared with control group, sample B group were significantly decreased RBC compared with control group. 5. All sample group ware decreased hemoglobin and hematocrit compared with control group. 6. All sample group ware increased total serum cholesterol compared with control group, sample B group were significantly decreased platelet compared with control group. 7. All sample group ware significantly decreased total serum protein level compared with control group. 8. All sample group ware increased total serum cholesterol compared with control group, sample B group were significantly increased total serum cholesterol level compared with control group. Conclusions : We thought that Mahwangkanghwal-tang(Mahuangqianghuo-tang) could be used for curing rheumatoid arthritis, anti-inflammatory effect was somewhat better in much than small dosage.

• Journal of Powder Materials
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• v.28 no.2
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• pp.120-126
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• 2021

In this study, AlSi10Mg alloy powders are synthesized using gas atomization and sieving processes for powder bed fusion (PBF) additive manufacturing. The effect of nozzle diameter (ø = 4.0, 4.5, 5.0 and 8.0 mm) on the gas atomization and sieving size on the properties of the prepared powder are investigated. As the nozzle diameter decreases, the size of the manufactured powder decreases, and the uniformity of the particle size distribution improves. Therefore, the ø 4.0 mm nozzle diameter yields powder with superior properties. Spherically shaped powders can be prepared at a scale suitable for the PBF process with a particle size distribution of 10-45 ㎛. The Hausner ratio value of the powder is measured to be 1.24. In addition, the yield fraction of the powder prepared in this study is 26.6%, which is higher than the previously reported value of 10-15%. These results indicate that the nozzle diameter and the post-sieve process simultaneously influence the shape of the prepared powder as well as the satellite powder on its surface.

• Journal of the Korean School Mathematics Society
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• v.24 no.4
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• pp.327-348
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• 2021

This study examines the effects of mathematics learning mentoring activities on mathematical knowledge for teaching (MKT) of pre-service mathematics teachers. We choose six pre-service mathematics teachers in the department of mathematics education at M University. The pre-service mathematics teachers conducted 1:1 mathematics learning mentoring for two hours at a times and twice a week for 15 weeks. The pre-service mathematics teachers submitted the mentor log, which recorded weekly learning and emotional observations. We collected the mentor log and the reflection log of pre-service mathematics teachers and the interviews with pre-service mathematics teachers. Based on the collected data, we analyzed the effects of MKT, the understanding of students, and pre-service mathematics teachers' introspection by mathematics learning mentoring. We obtained conclusions as follows. First, mathematics learning mentoring provides an opportunity for pre-service mathematics teachers to apply the theory of mathematical education to schools. Thus pre-service mathematics teachers express theoretical knowledge as practical knowledge. Second, mathematics learning mentoring helps pre-service mathematics teachers have the ability to understand students and provide opportunities to reflect on their attitudes as learners. Third, mathematics learning mentoring helps advance teaching activities by providing pre-service mathematics teachers with opportunities to reflect on their teaching activities. Finally, mathematics learning mentoring has positively influenced the change in pre-service mathematics teachers' beliefs and teaching intuition.

• Journal of the Korean School Mathematics Society
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• v.16 no.1
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• pp.157-185
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• 2013

This study was to investigate novice teachers' Specialized Content Knowledge for Teaching in High School Calculus Lessons. The lessons of two novice teachers in Kyunggi Do were observed from July, 2011 to Feb. 2012. All observed lessons were audeotaped and transcribed into word files. Their calculus lessons were analyzed into three kinds of knowledge consisting of SCKT. Their SCKT just copied the contents of the textbook and other additional SCKT were not found for teaching. Even though students asked a question that they did not understand, the teacher just repeated the previous contents that already he used. But this study included possible contents of SCKT within the areas these teachers covered so that teachers in school may use for teaching of Calculus. The novice teacher do not have sufficient experience, the program of the college of education and the contents of the teacher certificate-examination should include multi-dimensional approaches in SCKT to pre-service teachers in order to raise better specialized teachers in mathematics.

• Communications of Mathematical Education
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• v.26 no.3
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• pp.301-316
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• 2012

Ball, Thames & Phelps(2008) introduced the idea of Mathematical Knowledge for Teaching(MKT) teacher. Specialized Content Knowledge(SCK) is one of six categories in MKT. SCK is a knowledge base, useful especially for math teachers to analyze errors, evaluate alternative ideas, give mathematical explanations and use mathematical representation. The purpose of this study is to analyze the elementary teacher's SCK. 29 six graders made word problems with respect to division fraction $9/10{\div}2/5$. These word problems were classified four sentence types based on Sinicrope, Mick & Kolb(2002) and then representative four sentence types were given to 10 teachers who have taught six graders. Data analysis was conducted through the teachers' evaluation of the answers(word problems) and revision of students' mathematical errors. This study showed how to know meanings of fraction division for effective teaching. Moreover, it suggested several implications to develop SCK for teaching and learning.

• Research in Mathematical Education
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• v.19 no.2
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• pp.101-115
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• 2015

In the present paper, we argue any research concerning human knowledge construction, components, or types needs to clarify its epistemological stance regarding 'knowledge' in that such viewpoint might have much influence on the nature of knowledge the researcher sees and the way in which evidence for knowledge development is gathered. Thus, we suggest two alternative research groups who conducted their studies on mathematical knowledge for teaching with an explicit epistemological standpoint. We finalize our discussion by reviewing concrete examples in the previous literature on teacher knowledge of fraction conducted by the two groups.

• The Korean Journal of Food And Nutrition
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• v.6 no.1
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• pp.1-7
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• 1993

19 Samples of koji-starters using in brewing were collected from Korea and Japan, and then 31 strains of koji-molds were isolated from them. After Identification of the Isolate, rice koji was made with each strains, and its saccharogenic activity, dextrogenic activity, proteolytic activity, acid Producing ability, browning reaction and flavor were tested. Among 31 strains of isolates, 10 strains were Identified as Asp nwamori var. kawachii, 18 strains as Asp. oryzae, 3 strains as Asp. usamii mkt. shirousamii. The koji-starters made in Korea were composed of single species of koji-mold with same strain, but those made in Japan were composed of the mixture of different two species or the mixture of different 2 ∼4 strains in same species. Judging from amylolytic and proteolytic ability by species, Asp. awamori var. kawachii H1, I1 and 11, Asp. owsae J2, L2, M2, P3 and P4, and Asp. usamii writ. shirousamii S1 were better than the others. Mold strains isolated from Korean koji-starters were much lower in amylolytic or proteolytic activity than those from Japanese koji-starters. The typical characteristics for the 3 species of koji-molds were that Asp. awamori var. kawachii was strong in acid producing ability, but week in amylolytic and proteolytic ability, that Asp. owzae had strong amylolytic activity and good aroma, but produced little amount of acid, and that Asp. usamii mut. shirousamii had strong Proteolytic activity but some off-flavor.

• Korean Journal of Oriental Medicine
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• v.8 no.1
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• pp.45-53
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• 2002

Objectives : On the internet, the bibliographic information service systems of the theses for the degree of Korean medicine(KMT) have been builded by the National assembly library, the National library of Korea and the eleven central libraries of eleven colleges of Korean medicine in Korea(KMU). Because there was a lot of information of Korean medicinal research & development(R&D) in those KMT, the MKT are most valuable in the Korean medicinal R&D. This study was carried out to understand and analyze the information service systems of the theses of Korean medicine provided by those libraries. Methods : We collected the bibliographic information of KMT on the internet in the National assembly library, the National Library of Korea, KMU, and some references of KMT, and then made a comparison between the bibliographic information of KMT and those KMU about the simpleness of searching and the accuracy of the contents. Results : Many of the Korean medicinal information service systems of KMU are poor on the simpleness of searching and the accuracy of the contents. On the accuracy of the contents, the bibliographic information service systems of KMT mistakes about 20% because of misusing of a Chinese character, a rule of the initial sound of a syllable of the Korean alphabet, and an erroro of the term day on KMT.