• School Mathematics
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• v.9 no.1
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• pp.99-117
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• 2007

In this paper it is discussed how children develop their logical reasoning beyond difficulties in the process of making sense of division with decimals in the classroom setting. When we consider the gap between mathematics at elementary and secondary levels, and given the logical nature of mathematics at the latter levels, it can be seen as important that the aspects of children's logical development in the upper grades in elementary school should be clarified. This study focuses on the teaching and learning of division with decimals in a 5th grade classroom, because it is well known to be difficult for children to understand the meaning of division with decimals. It is suggested that children begin to conceive division as the relationship between the equivalent expressions at the hypothetical-deductive level detached from the concrete one, and that children's explanation based on a reversibility of reciprocity are effective in overcoming the difficulties related to division with decimals. It enables children to conceive multiplication and division as a system of operations.

• Journal of Animal Science and Technology
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• v.52 no.3
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• pp.191-198
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• 2010

A total of 96 non-lean-type (Yorkshire $\times$ Landrace) $\times$ Duroc gilts and barrows weighing approximately 80 kg were randomly allocated to 24 pens under a 2 (sex) $\times$ 3 [diet; 3.4, 3.2, and 3.0 Mcal DE/kg {'high'-, 'medium'-, and 'low'-energy diets (HE, ME, and LE), respectively}] factorial arrangement of treatments. All animals were slaughtered approximately at 115 kg, after which carcass quality traits and grades and physicochemical and sensory characteristics of the loin related to meat quality were analyzed. The ADG and gain:feed were not affected by the sex or dietary treatment, whereas ADFI was greater in the ME vs HE group. Backfat thickness was greater in barrows vs gilts and also in ME and HE vs LE only in barrows. Enumerated carcass marbling and quality grade, which were highly correlated (r=0.56; P<0.01), were greater in barrows vs gilts. Physicochemical characteristics including the color, pH, drip loss and contents of moisture, protein, and fat of fresh loin, as well as sensory characteristics of fresh and cooked loin, were not affected by the sex or dietary treatment, except for shear force for cooked loin which was greater (P<0.05) in LE and ME vs HE. In conclusion, it is thought that ME is comparable to HE in terms of the effect on growth and carcass quality of finishing pigs, but that the relative effect of LE vs ME needs to be further studied.

• Education of Primary School Mathematics
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• v.14 no.3
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• pp.261-275
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• 2011

We observed the process for solving linear equations of two 5th grade elementary students, who do not have any pre-knowledge about solving linear equation. The way of students' usage of fractional schemes and manipulations are closely observed. The change of their scheme adaptation are carefully analyzed while the coefficients and constants become complicated. The results showed that they used various fractional scheme and manipulations according to the coefficients and constants. Noticeably, they used repeating fractional schemes to establish the equivalence relation between unknowns and the given quantities. After establishing the relationship, equivalent fractions played important role. We expect the results of this study would help shorten the gap between the arithmetic and the algebraic thinking.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.13 no.5
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• pp.195-201
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• 2013

The government has invested much budget for 5years to do the Smart-education and operate digital textbook services since 2011. The private enterprises also decided to focus on constructing Smart learning system by investing much budget. If these systems are constructed nationwide and therefore can access to cyber university by using smart devices, we can reduce the information gap and study online lectures to get a grade whenever, whoever and wherever we want to. However, these convenient systems can cause serious problems like falsifying grades by hacking if security systems are weak. In this paper, we formulated cyber university which is secured in terms of security. For this, we simulated the smart-learning system which strengthened the security, considering code algorithm and encryption technique.

• Korean Medical Education Review
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• v.15 no.2
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• pp.87-92
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• 2013

The purpose of this study was to assess third-year medical students' competency for development or revision of the undergraduate curriculum and assessments. One hundred and twenty-seven third-year medical students at the Pusan National University were included in the study. After third- and fourth-year students took a common written examination, clinical performance examination (CPX), and objective structured clinical examination (OSCE) with common items as a summative assessment, the third-year students' competency was compared with 132 forth-year students' results. The correlation of the written examination and CPX/OSCE was analysed, and the summative results were compared with the grade point average (GPA) through the second year, CPX/ OSCE in the second year, and GPA in the clerkship. On the written examination, the third-year students' mean score was lower than the fourth-year students' by over 11 points, whereas the gap in the CPX/OSCE was 4 points and there was no difference in the OSCE. There was a moderate correlation between the written examination and the CPX/OSCE scores (R=0.371, p<0.01). The written examination was highly correlated with GPA through the second year, which mainly evaluated medical knowledge (R=0.771, p<0.01). A relatively high correlation was observed between CPX/OSCE scores and GPA in the clerkship (R=0.641, p<0.01). The summative CPX/ OSCE scores showed a moderate correlation with formative CPX/OSCE scores in the second year (R=0.464, p< 0.01). The third-year students' score was quite low on the written examination and slightly low on the CPX/OSCE compared to that of the fourth-year students. The written examination and CPX/OSCE cannot replace each other and should be combined with other methods of evaluation to measure competency. Early OSCE and workplacebased assessment should be useful in the early assessment of clinical skills competency.

• Journal of Educational Research in Mathematics
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• v.24 no.3
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• pp.359-374
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• 2014

Students' difficulties and errors in relation to mathematical proofs are worth while to say one of the dilemmas in mathematics education. The potential elements of their difficulty are scattered over the process of proving in geometry as well as algebra. This study aims to investigate whether middle school students understand the context of algebraic proof including literal expressions. We applied 24 third-grade middle school students a test item which shows a proof including a literal expression and missing the conclusion. Over the half of them responded wrong answers based on only the literal expression without considering its context. Three of them were interviewed individually to show their thinking. As a result, we could find some characteristics of their thinking including the perspective on proof as checking the validity of algebraic expression and the gap between proving and understanding of proof etc. From these, we also discussed about several didactical implications.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.10
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• pp.6134-6141
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• 2014

This study analyzed the gap in perception between communication with parents and filial piety according to the general characteristics of teenagers. The test subjects were high school students from academic and vocational school from different districts of Seoul. A survey was conducted from March to July of 2014 to 290 high school students. Data analysis was conducted on the SPSSWIN 18.0 program using a t-test, one-way analysis of variance, correlation analysis, and other tests. The empirical analysis of the experiments were verified at the significance level of 5%. First, communication with fathers differed significantly depending on the school division, economic class, religion; and communication with mothers differed significantly depending on school division, grade-level, academic performance, domestic discipline, and economic class. Second, the perception of filial piety showed a significant positive correlation with the communication with the mother; and with the communication with the father. The implication of this study is that better communication between the parents and teenagers correlate with the higher filial piety according to the general characteristics of teenagers, and should become a central material for policy.

• Journal of the Korean Society of Food Culture
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• v.11 no.5
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• pp.663-671
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• 1996

The purpose of this study was to compare high-school students importance and performance toward restaurant service attributes for the marketing strategy development. Specific objectives were to: a) investigate restaurant patronage characteristics of high school students; b) identify the difference of patronage behavior among three types of restaurants; and c) analyze the importance and performance among three types of restaurants. A questionnaire was developed and hand-delivered to 400 students enrolled 9th grade in 4 different high schools in Seoul. A total of 320 students (80%) was responded to this study. The questionnaire was composed of two parts with 47 restaurant service attribute statements. Results of this study were as follows: 1. A total of 57% was female and 61% of respondents spent less than ￦5,000 per week on eating out. 2. The frequency of visiting the low-priced restaurant was 8.9 times per week. 3. Reasons for being a patronage to low- (${\geq}$￦2,000) and mid-priced ( <￦2,000 and ${\geq}$￦5,000) restaurants were hunger, appointment, and seeking favorites with freinds but the reason for high-priced (<￦5,000) restaurants was celebrating special days with parents. 4. The main source of information for selecting restaurants was family and friends, T.V. advertising, and bulletin board. 5. For the low-priced restaurants, food, hygiene, price, and location were rated as important; location, price, menu, and food were rated as satisfied. 6. For the mid-priced restaurants, hygiene, food, price, and menu were rated as important; food, hygiene, service, and menu were rated as satisfied. 7. For the high-priced restaurants, hygiene, food, and atmosphere were rated as important; food, hygiene, atmosphere, and menu were as satisfied. 8. According to paired t-test, the score gap between importance and performance was the highest in the hygiene attribute; differences were high with the low-priced and low with high-priced restaurants.

• Journal of Welding and Joining
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• v.28 no.2
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• pp.32-38
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• 2010

In shipbuilding industry, welding position are usually flat and vertical position at the erection stage. Application of SAW and EGW for these positions makes it possible to achieve enhanced productivity and high quality. But owing to their large size and weight it is difficult to apply these techniques in short and narrow regions. To overcome this problem, our company developed light weight and compact size 4-axis welding carriage which perform 3D weaving. The purpose of this study is to explain the development and application of intelligent welding carriage using 3D weaving pattern that can fill a large amount of welds and thereby making it possible to achieve high quality of welding. This study shows 3D weaving pattern, development of weaving database, and skill of adaptive control response for the variable gap. Also, it shows the results of procedure qualification test for the AH-grade steel when applied to the intelligent welding carriage.

• Cross-Cultural Studies
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• v.33
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• pp.331-358
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• 2013

This paper looks into several aspects of linguistic behaviors attested in Korean and American English corpora. A special attention is paid to the areas of politeness phenomena, terms of address, power and solidarity, practice of flattery, and closely-related non-linguistic behaviors such as tipping and gift-giving conventions. An analysis of the data reveals that Korean society remains very much superior-oriented, non-egalitarian, non-democratic despite the pride and sense of accomplishment among the populace that the nation has achieved a satisfactory level of democracy. In particular, the following facts in Korean and the Korean society are exposed by an examination of the data: ${\bullet}$ There is a notional gap of positive politeness ${\bullet}$ Superiors enjoy an unfair advantage in the power and solidarity system ${\bullet}$ The terms of address system is set up to make a clear distinction between levels and the terms of address, in turn, dictate norms of expected behavior ${\bullet}$ The notion and practice of flattery heavily favors superiors ${\bullet}$ Non-linguistic acts of gift-giving and tipping are consistent with the examined social interactions As a result, all the benefits, emotional as well as material, are garnered by superiors. These facts may reflect the real Korea that people are used to being comfortable with, a pre-modern, feudalistic society, something akin to its kin in the north. We may proclaim that we aspire to a more democratic society. However, it appears Koreans, deep inside, may have been seeking a powerful dictator all along. These findings help provide a partial but insightful clue to the political puzzle: why Koreans grew uncomfortable with an egalitarian and democratic president and could not save him, but instead replaced him with a succession of a corrupted businessman and the authoritarian daughter of a former dictator. The flight to democracy has stalled in midair, not quite making the grade yet. There is plenty of linguistic evidence in Korean.