• Journal of The Korean Association For Science Education
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• v.29 no.8
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• pp.978-989
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• 2009

In this study, we investigated high school students' errors in constructing and interpreting graph on experimental results by students' science achievement level. Two tests regarding constructing and interpreting graph about 'the relationship between the pressure and volume of a gas' were administered to 11th-graders (N=140). Analysis of the results revealed that most students exhibited many errors in the processes of constructing and interpreting graph. In the processes of constructing graph, there were 16 types of errors on the categories of 'misinterpreting the variables', 'mis-marking the graphical elements', and 'misusing the data'. The students of lower achievement level had more errors than those of higher achievement level in the four error types, that is, 'missing the variables', 'representing the best fit line using a broken line', 'adding the data', and 'neglecting the data'. However, the results were reversed in the error type of 'not marking the origin.' In the processes of interpreting graph, there were 9 types of errors on 'misreading the data', 'wrong interpolation and extrapolation', and 'establishing the wrong relationship'. The students of lower achievement level had more errors than those in the higher achievement level in the error types of 'wrong interpolation' and 'misdescribing the relationship between variables'. Educational implications of the findings are discussed.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.10
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• pp.2500-2506
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• 2015

Proposal assessments for new weapon system development such as C4I system have been applying a qualitative assessment. The main problem of qualitative assessment is that the results vary depending on the evaluator's subjective preferences and priorities. Also, if there is no discrimination of technical skills degrade, the company will be selected by bid price regardless of technical power. In order to making a fairness, We need a method to compensate for the evaluator's subjectivity and to enhance discrimination. Previous standardization method is limited because targets of the proposal assessment are minority and have similar skill level. So, The new standardized evaluation methods applicable to the proposal was presented. This way is using the priority instead of the score and has better performance than existing methods as the target numbers are smaller.

• Convergence Security Journal
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• v.16 no.3_2
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• pp.13-23
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• 2016

North Korea had recently conducted the fourth nuclear test and ICBM tests, dared nuclear provocation targeting the Korea and the international community. It is determined based on experiments of nuclear and missile in progress in North Korea that the technical level of nuclear force reached the completion stage of standardization, lightweight, and variation. It is expected to become reality that North Korea executes the nuclear provocation targeting the Korea and the international community in the near future. Nuclear bomb is an absolute weapon that the logic of counterattack after allowing the first strike of the other party cannot be applied due to its tremendous destructive power. Therefore, as the opponent to North Korea that it decided to hold the nuclear, the exercise of anticipatory self-defense in order to guarantee a minimum of right to life is not a choice, but the only essential correspondence concept. At the moment that the North Korean nuclear provocation is expected in the near future, it shall be provided with competence to strike the origin region of provocation by forming a national consensus of preemptive strike enforcement. Also, in preparation for the fifth nuclear test of North Korea, which is anticipated, the national competence must be mobilize to be able to ensure the 'Nuclear Option' from the international community.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.5 no.1
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• pp.54-69
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• 1994

The purpose of present study was to develop the Korean Version of Luria-Nebraska Neuropsychological Battery for Children(LNNB-C), to examine the reliability of it, and to establish the norms for determining the probability of brain damage. The normative group used to standardize the Korean version of LNNB-C was composed of 147 children between the age of 8 and 12(body 74, girl 73). The clinical group consisted of 19 brain damaged, 16 ADHD, and 16 psychiatric controls. The inter-scorer reliability was 96.3%, indicating that the stability of the scoring system for the Korean version of LNNB-C is good. The reliability coefficients(Cronbach's ${\alpha}$) of LNNB-C scales were ranged .51 to .91, which are similar to those of original LNNB-C. To establish the norms for detecting brain damage, the means and standard deviations for normative group were used to calculate T-scores for each scale. To determine a critical level that could successfully predict a normal child's average score at a given age, first the average score of normative group was calculated, and this score was then entered a regression equation with age to predict the average(baseline) acore. Finally, some issues on constructing the Korean version of LNNB-C and the cultural differences between Korean and American children in performing LNNB-C were discussed.

• 한국노년학
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• v.29 no.3
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• pp.971-986
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• 2009

This research investigated how the participation of various social activities affects cognitive function in middle-aged and elderly population. To examine the relation between the participation of various social activities and cognitive function, we used data from the Korean Longitudinal Study of Ageing. Social activities were classified into four types as religious ritual, leisure, public association and ascriptive association activities, and MMSE-K score was used to measure cognitive function. Results from multiple regression analyses after adjusting for socio-economic status and health status show that the participation in religious and leisure activities have positive effects on cognitive function in middle-aged and elderly population. Participation in leisure activities in middle-aged male group helps preserve cognitive function, and leisure activity and ritual activity are significantly related to cognitive function in middle-aged female group. Meanwhile the participation in religious and leisure activities have positive effects on cognitive function in elderly male and female group. Based on these findings, we suggest that various programs to support the participation of elderly population in social activities should be developed for healthy life for the elderly.

• Journal of The Korean Association For Science Education
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• v.30 no.4
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• pp.452-471
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• 2010

As the Korean College scholastic Ability Test (CSAT) has been implemented for 17 years since 1994, it is becoming more and more difficult to make new items that haven't been previously used to measure students' thinking ability. Therefore, it is necessary to keep conducting research on making new test items that can measure students' scholastic ability reliably. For this reason, multiple choice items on the Japanese university entrance exam, which is a Japanese National Center Test for University Admissions (NCTUA) equivalent of CSAT, were analyzed in order to draw implications for CSAT item development. In this study, we analyzed the Japanese NCTUA administered in January 2009 to investigate the structure of its science test. We also analyzed the NCTUA items by the domains of contents and behaviors, and tried to predict item difficulty from the perspective of Korean applicants. Major findings are as follows: Most NCTUA items measure understanding knowledge or low level thinking ability. Also the alloted time for each item is longer than CSAT. The number of test items, and the number of choice and alloted points for each item are diverse, unlike CSAT. The number of items using real-life materials are much more, but the items are not rigorous in sentence expression compared to CSAT. And the difference of difficulty level among science tests were larger with reference to CSAT. Also science score is required for most applicants regardless whether they are taking liberal arts or going onto the science track.

• The Journal of Engineering Geology
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• v.24 no.1
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• pp.101-110
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• 2014

This study presents the results of a regression analysis of the point-load strength ($I_{s(50)}$) and the uniaxial compressive strength (UCS) of granites in Korea. The regression was carried out for three cases using the least-squares method, reclassifying the granite samples based on their physical properties. The first regression analysis through the origin according to the weathering grade did not give a result with a sufficient degree of confidence, due to the small number of samples. However, the general trend of the correlation between UCS and $I_{s(50)}$according to weathering grade shows that the slope of the linear regression for weathered granite is steeper than that for fresh granite. The second analysis was a simple linear regression for all the granite samples using the least-squares method as well as a linear regression using the bootstrap resampling method in order to increase the confidence level and the accuracy of the regression results. The third regression considered the average strength of granite groups reclassified according to physical properties. These linear regression analyses yielded linear regression equations with slopes of 14 and small standard deviations being similar to values reported in previous studies on Korean granites, but whose intercept values range from 16 to 43 and have a larger standard deviation than those of the present study. In conclusion, it would be advisable to estimate UCS from $I_{s(50)}$, considering the error range derived from the deviation of the regression equations.

• Journal of the Korea institute for structural maintenance and inspection
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• v.26 no.4
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• pp.1-10
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• 2022

In this study, to evaluate the possibility of using a steel spring as a displacement-dependent damping device, tensile loading and cyclic loading tests were performed. The main experimental variables were the type of steel (SAE9254 and SS275), the spring constant (700 N/mm, 1,000 N/mm, and 1,400 N/mm), and the presence or absence of heat treatment for SAE9254. As a result of the tensile test, the ratios of the measured spring constant to the design spring constant of the steel springs made with SAE9254 ranged from 1.08 to 1.13, while the ratios of the design spring constant and the measured spring constant of the steel springs made with SS275 ranged from 0.86 to 0.97. After yielding, the slope values of the load-displacement curve of the SAE9254 with/without heat treatment were about 240~251 N/mm and 92 N/mm, respectively, but the slope values of the load-displacement response of SS275 were almost zero. According to the uniaxial cyclic loading test results, all specimens were satisfied with three conditions for a displacement-dependent damping device in KDS 41 17 00 (2019): the maximum force and minimum force at zero displacement, the maximum force and minimum force at the maximum displacement, and the energy dissipation capacity. In addition, the equivalent damping ratios of steel springs made with SAE9254(non-heat treatment) and SS275 were approximately 2.8 times and 1.9 times greater, respectively, than that of steel springs made with SAE9254.

• The Journal of Korean Society for Radiation Therapy
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• v.23 no.2
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• pp.97-102
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• 2011

Purpose: IMRT QA using 2Dimensional array detector is carried out with condition for discrete dose distribution clinically. And it can affect uncertainty of evaluation using gamma method. We analyze gamma index variation according to grid size and suggest validate range of grid size for IMRT QA in Hospital. Materials and Methods: We performed QA using OniPro I'mRT system software version 1.7b on 10 patients (head and neck) for IMRT. The reference dose plane (grid size, 0.1 cm; location, [0, 0, 0]) from RTP was compared with the dose plane that has different grid size (0.1 cm, 0.5 cm, 1.0 cm, 2.0 cm, 4.0 cm) and different location (along Y-axis 0 cm, 0.2 cm, 0.5 cm, 1.0 cm). The gamma index variation was evaluated by observing the level of changes in Gamma pass rate, Average signal, Standard deviation for each case. Results: The average signal for each grid size showed difference levels of 0%, -0.19%, -0.04%, -0.46%, -8.32% and the standard deviation for each grid size showed difference levels of 0%, -0.30%, 1.24%, -0.70%, -7.99%. The gamma pass rate for each grid size showed difference levels of 0%, 0.27%, -1.43%, 5.32%, 5.60%. The gamma evaluation results according to distance in grid size range of 0.1 cm to 1.0 cm showed good agreement with reference condition (grid size 0.1 cm) within 1.5% and over 5% in case of the grid size was greater than 2.0 cm. Conclusion: We recognize that the grid size of gamma evaluation can make errors of IMRT QA. So we have to consider uncertainty of gamma evaluation according to the grid size and apply smaller than 2 cm grid size to reduce error and increase accuracy clinically.

• 대한공업교육학회지
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• v.44 no.2
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• pp.104-122
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• 2019

In the era of the fourth industrial revolution, maker education is drawing attention as a method of student-led education. At a time when interest in maker education is also growing in technology education, figuring out what stage of concern(SoC) a middle school technology teacher is critical to effective implementation. This study analyzed SoC in maker education by layer sampling among 400 middle school technology teachers using Concerns-based adoption model. SoC was then obtained by measuring the origin using the SoCQ and then presenting it as a SOCQ profile. Gender, training experience with two lower variables were analyzed using t verification, working cities, teaching experience with more than three lower variables were analyzed using one-way ANOVA. Studies showed that SoC in maker education of middle school technology teachers showed the most similar characteristics to that of non-users. The difference in concern depending on gender was that male teachers were more concerned in maker education than female teachers. The difference in concern depending on the working city was that teachers working in the township were more concerned in the maker education than teachers working in the large city, and the difference in concern depending on the teaching career was higher among teachers with middle experience than those with low and high experience. There was also a higher stage of concern in maker education than in teachers without training experience. Therefore, it is necessary to provide middle school technology teachers with an introduction to the maker education and various information, teaching, learning and evaluation data to enhance overall concern and to support the use and evaluation of the maker education in the classroom by providing various teacher training and consulting on the maker education in the future. Further, through further study, we should conduct study that analyzes both Stage of Concern, Level of Use and Innovation Configuration, to put in the effort for effective settlement of maker education.