• Journal of the Korea Convergence Society
• /
• v.8 no.3
• /
• pp.123-131
• /
• 2017

This study is to find the weaknesses in drug dose calculations of nursing students by analyzing their general characteristics, confidence(C), performances in classes(PC) and exam sheets of drug dose calculations. The data were analyzed using SPSS 19.0. There was no significant difference between male and female students in simple calculation ability(SCA), but male students' mean scores were higher in applied calculation ability(ACA) and accuracy on calculation(AC). There were no significant differences in calculation abilities according to high school departments. And students were weak in questions which are needed ACA. The explanation rate of C on PC and PC on AC were 4.2% and 3.2% respectively, so there were weak positive effects from C to PC, and PC to AC. This study suggests that there is a need to develop and implement an intervention program according to students' abilities to increase AC, C, and PC by studying math on an ongoing basis. This study needs to be cautious in generalizing, because the data set was limited to nursing students from one university.

• Journal of People, Plants, and Environment
• /
• v.23 no.3
• /
• pp.321-332
• /
• 2020

Background and objective: The concept of 'money' in the numbers and operations domain is a fundamentally necessary domain of economic life. This study was conducted to examine the effects of a horticulture-mathematics integration program on mathematical attitude and money calculating ability of high school students with intellectual disabilities. Methods: We analyzed the changes in the mathematical attitude and money calculating ability of students with mild intellectual disabilities in S special school in the city of D, Republic of Korea, with 12 students in the control group and 12 students in the experimental group, from August 27 to October 29, 2019. Results: The results of the comparison showed no statistically significant changes in the three items of mathematical attitude for the control group, while the experimental group, which took part in the horticulture-mathematics integration program, showed statistically significant differences across all three items, such as self-concept about the subject (p = .003), attitude toward the subject (p = .004), and study habit related to the subject (p = .012). The horticulture-mathematics integration program, which was developed by integrating horticultural activities and the mathematics curriculum, used plants and horticultural activities to provide students with positive experiences in mathematics. These included the sense of closeness, curiosity, interest, attention, and enjoyment, leading to positive changes in mathematical attitude. In terms of money calculating ability, both the control group and experimental group showed statistical differences across the three items, but the experimental group showed greater degrees of increase, 15.0 or more, in the scores compared to the control group. Conclusion: These results suggest that utilizing horticultural materials as a part of purchase learning programs with elements of money calculation chapters in the mathematics curriculum could lead to the improvement of students' ability in money calculation. These positive changes are thought to be related to the high degrees of interest in horticulture among students, which led to active participation in the program and enabled the simple and repeated purchase activities in the program to generate positive changes in the money calculation ability of the students.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2004.10a
• /
• pp.198-202
• /
• 2004

This study proposes a new optimization algorithm which is combined with genetic algorithm and ANOM. This improved genetic algorithm is not only faster than the simple genetic algorithm, but also gives a more accurate solution. The optimizing ability and convergence rate of a new optimization algorithm is identified by using a test function which have several local optimum and an optimum design of rocker arm shaft. The calculation results are compared with the simple genetic algorithm.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.29 no.6 s.237
• /
• pp.835-841
• /
• 2005

This study proposes a new optimization algorithm which is combined with genetic algorithm and ANOM. This improved genetic algorithm is not only faster than the simple genetic algorithm, but also gives a more accurate solution. The optimizing ability and convergence rate of a new optimization algorithm is identified by using a evaluation function which have several local optimum and an optimum design of rocker arm shaft. The calculation results are compared with the simple genetic algorithm.

• Bulletin of the Korean Chemical Society
• /
• v.25 no.2
• /
• pp.253-259
• /
• 2004

Some new topological indices based on the distance matrix and Randic connectivity (as graph invariants) are proposed. The calculation of these indices is simple and they have good discriminating ability toward alkanes. Incorporating the number of carbon atoms to one of the calculated indices gives a highly correlating topological index (Sh index) which found to correlate with selected physicochemical properties of wide range of alkanes, specially, their boiling points. Most of the investigated properties are well modeled (with $r^2$> 0.99) by the Sh index. Meanwhile, the resulting regressions were compared with the results based on the well-established Randic and newly reported Xu indices and, in most cases, better results were obtained by the Sh index. Moreover, multiple linear regression analysis of the alkane properties via calculated indices gives highly correlating models with low standard errors.

• International Journal of Aeronautical and Space Sciences
• /
• v.18 no.2
• /
• pp.186-196
• /
• 2017

In order to resolve the trimming difficulty in rotor CFD calculations, a high-efficiency and improved "delta trim method" is established to compute the blade control settings that are necessary to identify the blade motion. In this method, a simplified model which combines the blade element theory and different inflow models is employed to calculate the control settings according to the target aerodynamic forces, then it is coupled into a CFD solver with unsteady Navier-Stokes equations by the delta methodology, which makes the control settings and aerodynamics calculated and updated in the meantime at every trim cycle. Different from the previous work, the current research combines the inflow model based on prescribed wake theory. Using the method established, the control settings and aerodynamic characteristics of Helishape 7A, AH-1G and Caradonna-Tung rotors are calculated. The influence of different inflow models on trimming calculations is analyzed and the computational efficiency of the current "delta trim method" is compared with that of the "CFD-based trim method". Furthermore, for the sake of improving the calculation efficiency, a novel acceleration factor method is introduced to accelerate the trimming process. From the numerical cases, it is demonstrated that the current "delta trim method" has higher computational efficiency than "CFD-based trim method" in both hover and forward flight, and up to 70% of the amount of calculation can be saved by current "delta trim method" which turns out to be satisfactory for engineering applications. In addition, the proposed acceleration factor shows a good ability to accelerate the trim procedure, and the prescribed wake inflow model is always of better stability than other simple inflow models whether the acceleration factor is utilized in trimming calculations.

• Journal of Elementary Mathematics Education in Korea
• /
• v.20 no.3
• /
• pp.479-498
• /
• 2016

Time is important in children's lives since their preschool years. However, previous studies indicate that many children struggle with the acquisition of time concepts. Also teachers do not know how to help them. This study aims to investigate elementary school students' understanding about time and induce its educational implications. To do this, about 130 children from first to fifth grades were tested for their ability to recognize(read and record) the analogue and digital times and to solve elapsed-time problems. The results showed that even first graders were able to read and record the minute times on digital clocks. And second graders were able to read and record the minute times on analogue clocks. Therefore, the ability to recognize analogue times was mastered by second grade. In case of the elapsed-time problems, there was statistically significant difference according to school years or types of problems. Students were successful in solving simple problems. However, the problems that include regrouping hour and minute remained difficult even for the older children. Based on these results, we made a few suggestions for teaching practice about time.

• Education of Primary School Mathematics
• /
• v.20 no.4
• /
• pp.253-266
• /
• 2017

The purpose of the study was to investigate the perceptions of Elementary school teachers on mathematics instruction. To do this, 7 test items were developed to obtain data on teacher's perception of mathematics instruction and 73 teachers who take mathematical lesson analysis lectures were selected and conducted a survey. Since the data obtained are all qualitative data, they were analyzed through coding and similar responses were grouped into the same category. As a result of the survey, several facts were found as follow; First, When teachers thought about 'mathematics', the first words that come to mind were 'calculation', 'difficult', and 'logic'. It is necessary for the teacher to have positive thoughts on mathematics and mathematics learning, and this needs to be stressed enough in teacher education and teacher retraining. Second, the reason why mathematics is an important subject is 'because it is related to the real life', followed by 'because it gives rise to logical thinking ability' and 'because it gives rise to mathematical thinking ability'. These ideas are related to the cultivating mind value and the practical value of mathematics. In order for students to understand the various values of mathematics, teachers must understand the various values of mathematics. Third, the responses for reasons why elementary school students hate mathematics and are hard are because teachers demand 'thinking', 'because they repeat simple calculations', 'children hate complicated things', 'bother', 'Because mathematics itself is difficult', 'the level of curriculum and textbooks is high', and 'the amount of time and activity is too much'. These problems are likely to be improved by the implementation of revised 2015 national curriculum that emphasize core competence and process-based evaluation including mathematical processes. Fourth, the most common reason for failing elementary school mathematics instruction was 'because the process was difficult' and 'because of the results-based evaluation'. In addition, 'Results-oriented evaluation,' 'iterative calculation,' 'infused education,' 'failure to consider the level difference,' 'lack of conceptual and principle-centered education' were mentioned as a failure factor. Most of these factors can be changed by improving and changing teachers' teaching practice. Fifth, the responses for what does a desirable mathematics instruction look like are 'classroom related to real life', 'easy and fun mathematics lessons', 'class emphasizing understanding of principle', etc. Therefore, it is necessary to deeply deal with the related contents in the training courses for the improvement of the teachers' teaching practice, and it is necessary to support not only the one-time training but also the continuous professional development of teachers.

• Journal of the Korean Chemical Society
• /
• v.55 no.6
• /
• pp.1030-1041
• /
• 2011

We investigated the understanding of pre-service science teacher about the chemistry concept of middle school curriculum using some items in National Assessment of Educational Achievement and analyzed the result according to background variables of pre-service science teacher. The result was that there were some pre-service science teachers who select incorrect answer at all items, pre-service science teachers don't fully understand the concept needed to solve item. And the percentage of correct answer at some items was low regardless of selection of chemistry as an elective subject at CSAT(College Scholastic Ability Test). We found some facts through the depth interviews to find the cause of the result. First, the misconception acquired in middle school days is tend not to change until college student. Second, the formation of misconception is affected by the study habit with which solve problem by simple calculation and memory without essential understanding. Third, the study habit with which solve problem by simple calculation and memory without essential understanding could not replace misconceptions acquired in middle school days with scientific concept regardless of selection of chemistry as an elective subject at CSAT.

• Education of Primary School Mathematics
• /
• v.14 no.2
• /
• pp.165-185
• /
• 2011

The purpose of this study is to confirm the effects of the learner-centered instruction based on constructivism on learners' reasoning ability and their achievements which is closely related to reflective abstracting ability. To do it, learner-centered instructions for division was implemented, recall test, generation test, content reasoning test I and II were carried out. The following conclusions were drawn from the data we got. Experimental group(EG) improved their reasoning ability, while comparison group(CG) did not. EG showed statistically significant difference in the achievements of the contents learned in comparing with CG, and the difference in the achievements of the contents unlearned in the treatment in comparing with CG was higher than the one. In addition, the comparisons of the subgroups(high, middle, and low) between EG and CG showed that the treatment had a positive influence on the achievement to all subgroups in EG. That is, the treatment was effective for unable learners. Finally, EG showed statistically significant difference in the sub-domain of simple calculation which might be considered as the benefits of the treatment of the CG as well as in the sub-domain of concept and principle.