• The Mathematical Education
• /
• v.46 no.3
• /
• pp.273-292
• /
• 2007

The purpose of this study was to find out how second, fourth and sixth graders understood the main contents related to spatial sense in the Seventh National Mathematics Curriculum. For this purpose, this study examined students' understanding of the main contents of congruence transformation (slide, flip, turn), mirror symmetry, cubes, congruence and symmetry. An investigation was conducted and the subjects included 483 students. The main results are as follows. First, with regards to congruence transformation, whereas students had high percentages of correct answers on questions concerning slide, they had lower percentages on questions concerning turn. Percentages of correct answers on flip questions had significant differences among the three grades. In addition, most students experienced difficulties in describing the changes of shapes. Second, students understood the fact that the right and the left of an image in a mirror are exchanged, but they had poor overall understanding of mirror symmetry. The more complicated the cubes, the lower percentages of correct answers. Third, students had a good understanding of congruences, but they had difficulties in finding out congruent figures. Lastly, they had a poor understanding of symmetry and, in particular, didn't distinguish a symmetric figure of a line from a symmetric figure of a point.

• Journal of Korean Foot and Ankle Society
• /
• v.23 no.4
• /
• pp.143-148
• /
• 2019

Although many patients who undergo bunion repair do well and have satisfactory results, a critical evaluation of these results shows the potential for improvement. Metatarsal deformity of the hallux valgus is a 3-dimensional deformity, including rotation in the coronal plane. Theoretically, it is important to understand the 3-dimensional displacement of the first metatarsal for correcting the deformities of valgus rotation in the frontal plane. Yet the current methods of metatarsal osteotomy principally attempt to correct the deformity in the transverse plane. The modified technique for the Lapidus procedure can be used in a variety of hallux valgus conditions and severities, and the early results suggest that a powerful correction can be maintained. In addition, efforts have been made to correct the 3-dimensional deformity by performing metatarsal shaft osteotomy. In the case of degenerative arthritis, first metatarsophalangeal joint arthrodesis is a good option to correct the 3-dimensional deformation. Correction of the 3-dimensional deformity, including a rotational deformity in the frontal plane of the metatarsals, should be considered when selecting surgical treatment and is essential for achieving a good prognosis for patients with hallux valgus. This article reviews the classification and treatment of hallux valgus for correction of the 3-dimensional deformity.

• Journal of Microbiology and Biotechnology
• /
• v.10 no.5
• /
• pp.690-693
• /
• 2000

Efficient intron deletion with the correct splicing of the two exons of the human proinsulin gene was accomplished by a novel stepwise method using genomic DNA [5]. The two exons were separately amplified in two steps, using the second step primers that incorporated additional bases complementary to the other exon. The fragments were combined in a third PCR reaction. Cloning and sequencing of the PCR product demonstrated the correct splicing of the two exons. Expression studies, using the pET9a vector, revealed a protein band with the correct size with respect to human proinsulin as confirmed by SDS-PAGe and Western blot. Proinsulin concentration was estimated to be around 200 mg per liter culture, expressed as inclusion bodies. Protein secretion to the culture medium and periplasmic space was achieved by cloning in the pEZZ18 vector.

• Journal of Korean Elementary Science Education
• /
• v.24 no.1
• /
• pp.43-50
• /
• 2005

This study examined the effects of the result of ascertaining predictions on cognitive conflict and conceptual change when students teamed the concept of weightlessness. Participants were 200 pre-service elementary teachers. They answered the pretest composed of two items. Through the demonstration on either of two items of the pretest, they identified whether their predictions were correct or not. In addition, students' cognitive conflicts were measured. After brief instructional treatment, the posttest was conducted. The results of this study are as follows: The more students who identified their own predictions on the experiment were incorrect there were, the more effective it was on cognitive conflict and conceptual change. And cognitive conflicts and conceptual changes of students who identified that their predictions were incorrect were generated meaningfully more than those of students who identified that their predictions were correct. From these results, it is concluded that students who identified that their predictions were correct experience cognitive conflicts, but their cognitive conflicts and conceptual changes were smaller than those of students who identified that their predictions were incorrect.

• Journal of Information Processing Systems
• /
• v.10 no.4
• /
• pp.602-617
• /
• 2014

The performance of a cognitive radio network (CRN) solely depends on how precisely the secondary users can sense the presence or absence of primary users. The incorporation of a spatial false alarm makes deriving the probability of a correct decision a cumbersome task. Previous literature performed this task for the case of a received signal under a Normal probability density function case. In this paper we enhance the previous work, including the impact of carrier frequency, the gain of antennas on both sides, and antenna heights so as to observe the robustness against noise and interference and to make the correct decision of detection. Three small scale fading channels: Rayleigh, Normal, and Weibull were considered to get the real scenario of a CRN in an urban area. The incorporation of a maximal-ratio combining and selection combing with a variation of the number of received antennas have also been studied in order to achieve the correct decision of spectral sensing, so as to serve the cognitive users. Finally, we applied the above concept to a traffic model of the CRN, which we based on a two-dimensional state transition chain.

• The Mathematical Education
• /
• v.51 no.4
• /
• pp.395-413
• /
• 2012

National Assessment of Educational Achievement(NAEA) is important standard reference to become the basic data for confirming the effect of the curriculum administrated and the educational policies put in force presently and preparing the new curriculum and educational policies. In this paper, we looked into the mean and standard deviation of the calibrated score of whole group and male/female students, the correct answer ratio of each performance level and the correct answer ratio of each content domain, etc. in the results of NAEA at 6th elementary school. The analytic objects are 2010 and 2011 NAEA that are changed into complete enumeration survey and the standard reference prepared on the basis of the new calibrated score is applied to. And we analysed and compared correct answer ratio of the each content domain and each item to conform the difference between male and female students. On the basis of the these informations, we investigated that here is what kind of characteristics and trends to the whole group and what kind of suggestions to the teaching-learning. And we were going to provide the information of the needs to understand which content of mathematics is needed and which thinking methods are needed.

• Journal of Korean Elementary Science Education
• /
• v.40 no.1
• /
• pp.36-54
• /
• 2021

The purpose of this study was to investigate pre-service elementary school teachers' understanding about alternative energy and to identify their alternative conceptions. The two-tier instrument had been developed by Cheong et al. (2015) were used for this study. Twelve items from the instrument consisted of four categories: 'source of alternative energy', 'greenhouse gas emission', 'cost in electricity and construction' and 'advantages and disadvantages'. One hundred and fifteen pre-service elementary school teachers were participated in online survey during the semester. The results analyzed using SPSS 26.0. were as follows: First, the correct response rate varied depending on the content of item. Items related to characteristics and advantages & disadvantages of alternative energy showed high percentage of correct answers. Whereas, items regarding the principles of alternative energy showed relatively low percentage of correct answers. Second, there are some items showing statistically meaningful differences according to students' high school track. Nevertheless, there are no significant differences in overall. Third, we identified twelve alternative conceptions about alternative energy from students' answer distribution. Educational implications were discussed based on the results.

• Journal of Korea Multimedia Society
• /
• v.24 no.6
• /
• pp.805-814
• /
• 2021

Push-ups are one of the body exercises that can be easily measured anytime, anywhere. As one of the most widely used techniques as a test tool for evaluating physical strength, they are broadly used in various fields, especially in fields that require physical ability to estimate, such as military, police, and firefighters. However, social distancing is currently being implemented, and the issue of fairness has been steadily raised due to subtle differences between measurement. Accordingly, in this paper, the correct posture for each individual was photographed and learned by a high-performance computer, and the result was derived by comparing it with the case of performing the incorrect posture of the individual. If method is introduced into the physical fitness evaluation through the proposed method, the individual takes the correct posture and learns the photographed photo, and measures the posture with several images taken during a given time. Through this, it is possible to measure more objectively because it measures with the merit that can be measured even in the present situation and with one's correct posture.

• Journal of Korean society of Dental Hygiene
• /
• v.21 no.2
• /
• pp.141-150
• /
• 2021

Objectives: This study aimed to investigate oral health-related knowledge in adults and to determine the effect of oral health knowledge on correct brushing and use of dental care products. Methods: The subjects of this study were 552 adults who visited dental clinic, and a self-administered questionnaire was administered. Statistical analysis was performed using the t-test, ANOVA, and multiple regression using the SPSS statistics program (ver. 23.0, IBM Co., Chicago, IL, USA). Results: The oral health knowledge level, correct brushing, and dental care product usage scores were found to be positively correlated (r=0.015, 0.016), and both correlation coefficients were statistically significant (p<0.05). Oral health knowledge was found to have a significant effect on correct brushing among oral health promotion behaviors (β=0.116, p=0.006), but it was not found to have a significant effect on the use of dental care products (β=0.053, p=0.214). Conclusions: Oral health promotion behavior is closely related to oral health knowledge, and it is thought that oral health promotion behavior can be improved by raising oral health knowledge levels.

• East Asian Journal of Business Economics (EAJBE)
• /
• v.10 no.1
• /
• pp.95-108
• /
• 2022

Purpose - This study attempts a multifaceted analysis utilizing the Chinese test takers' results of the Economy & Business Aptitude Test. Since Chinese students study socialist theories of economics along with market-based ones, comparing Chinese university students' basic knowledge of economics and business and its application to those of Korean test takers is also very meaningful from the perspective of economics education research. Research design, data, and methodology - This study investigates the results on the test of economy and business understanding between Korea and China. For comparison of the result, we conducted MK-TEST for two universities in China. Result - This study finds that the average correct answer rate of Korea is higher than one of China according to the overall results. The average difference rate is about 15% between Korea and China. More concretely, the correct answer rate of business area is higher than one of economy area, identifying them by subject area. Conclusion - According to the results, this study can infer that there are no or little differences in the ability of examinee to solve applied questions between Korea and China and the differences of the scope and emphasis point in an academic curriculum between both countries might bring these kinds of results. Finally, Chinese students shows higher correct answer rate to the questions about the economy issues and policies related to China than one of Korea examinee.