• Bulletin of the Society of Naval Architects of Korea
• /
• v.15 no.4
• /
• pp.1-5
• /
• 1978

The preliminary ship design step is made into a non-linear programming(NLP) problem. And using SUMT-exterior method and Hook Jeeves pattern search, the optimum ship characteristics are determined for the case where the ship is built in Korea and is operated by Koreans. Three programs for bulk carrier, tanker, and container ship are constructed and several sensitivity tests are performed. The result has little difference from the results of the other papers, but for high interest rate of return, slightly larger and faster ship is superior, and for low labour costs, slightly smaller and slower ship is superior.

• Knowledge Management Research
• /
• v.20 no.1
• /
• pp.1-26
• /
• 2019

This tutorial introduces procedures and methods for performing structural equation modeling using R. For this, we present the whole process of analyzing the structural equations model from the confirmatory factor analysis to the path diagram generation using the lavaan package, which is relatively well evaluated among the R packages supporting the structural equation modeling, together with the R program codes. Considering that research applying structural equation modeling techniques is the mainstream in a variety of social sciences, including business administration, and that there is growing interest in open source R, this tutorial focuses on researchers who are looking for alternatives to traditional commercial statistical packages and is expected that it will be a useful guidebook for them.

• Knowledge Management Research
• /
• v.20 no.2
• /
• pp.1-24
• /
• 2019

This tutorial introduces procedures and methods for performing structural equation modeling using R. To do this, we present advanced analysis methods based on structural equation model such as mediation effect analysis, moderation effect analysis, moderated mediation effect analysis, and multiple-group analysis with R program code using R lavaan package that supports structural equation modeling. R is flexible and scalable, unlike traditional commercial statistical packages. Therefore, new analytical techniques are likely to be implemented ahead of any other statistical package. From this point of view, R will be a very appropriate choice for applying new analytical techniques or advanced techniques that researchers need. Considering that various studies in the social sciences are applying structural equations modeling techniques and increasing interest in open source R, this tutorial is expected to be useful for researchers who are looking for alternatives to existing commercial statistical packages.

• The Journal of Korean Association of Computer Education
• /
• v.18 no.3
• /
• pp.49-57
• /
• 2015

The purpose of this study is to provide considerations through investigation and analysis about non-computer major learners' difficulties in computational thinking education. In recent, the importance of human resources development in convergence based on computational thinking is increasing internationally and a Korean university is selecting CT as a mandatory subject. I taught CT with Scratch at C university in Seoul for two semesters in 2014 and investigated and analyzed what difficulties non-Computer majors felt in the process of CT education. The result showed they felt the following some difficulties in order: the concept of variable and list; to think a idea and implement it; which commands should be selected. The pleasure and the interest can be apply to decrease difficulty, because they affect self-programming ability and self-CT capability each other statistically. Although Scratch is an easy and an intuitive programming language, it is needed to consider to provide appropriate learning time to student for using and applying commands.

• Journal of the Korea Society of Computer and Information
• /
• v.22 no.1
• /
• pp.123-134
• /
• 2017

The ability to use information technology has become increasingly important as technological advances continue to sweep through the computing world, and education for improving computational thinking has become globally instituted. In South Korea, informatics subjects have been modified in the 2015 curriculum and are now compulsory in primary and secondary education. However, despite substantial financial investment and numerous studies promoting informatics education, there continues to be a serious lack of pre-service teachers capable of teaching computational thinking. This study investigated pre-service teacher programming education using App Inventor, their perceptions of App Inventor, and how use of the program affected teacher problem-solving abilities and self-efficacy. In the pre-test, the control group and experimental group showed no statistically significant difference; however, the post-test revealed that the two groups showed statistically significant differences in problem-solving skills and self-efficacy. The participants initially showed interest in using App Inventor; however, after practice-teaching and project-based learning, the participants demonstrated a growing negativity toward the program when they made errors and the functional limits of App Inventor became apparent. Although most participants stated that they would not use App Inventor in their classes, the positive statistically significant differences in problem-solving skills and self-efficacy indicate that this study could be utilized as a basis for building a teaching-learning program using App Inventor and creating an educational plan for teaching computational thinking.

• Proceedings of The KACE
• /
• 2017.08a
• /
• pp.121-124
• /
• 2017

초등 교육과정에 소프트웨어 교육 내용이 포함되는 2015 개정 교육과정의 시행을 앞두고, 학교 현장의 교사들은 이에 대한 지도 준비 수준이 낮으며 소프트웨어 교육 관련 교수 학습 자료도 부족하다고 느끼고 있었다. 이에 본 논문에서는 체험을 주 내용으로 하는 초등학교 프로그래밍 영역에 활용이 가능한 웹캠 기반 스크래치 프로그래밍 교육 콘텐츠를 개발하였다. 이 때 프로그래밍 흥미를 높일 수 있는 방법으로 웹캠을 사용하여 사용자의 움직임과 상호작용이 가능한 콘텐츠를 제작하였으며 총 10차시로 구성하였다. 추후 본 논문에서 제안한 교육 콘텐츠를 초등학생들에게 적용하여 교육적 효과를 검토할 것이다.

• Journal of the Korean School Mathematics Society
• /
• v.2 no.1
• /
• pp.181-195
• /
• 1999

This research is produced as a applet of learning materials, and is made with the internet languages HTML, Java, and NamoWebeditor. It contains "Greatest Common Divisor and Least Common Multiple", "Parallel translation of function of second order", "Pythagoras Theorem", which is the current middle school mathmatics textbook for third graders. The keynote of this research is that the students can study individually through logging into the internet on their own computers; the program is made using graphics and animation on order to develop the learners′ interest in mathematics. I hope that this research can supplement our currently insufficient internet educational data.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.21 no.47
• /
• pp.101-112
• /
• 1998

Recently, researchers show growing interest on product quality characteristic dependence and designing acceptance sampling plans under the quality dependence. This research intends to resolve a few theoretical and practical questions for better application of acceptance sampling when the quality characteristic of product items exhibits a statistical dependence and samples are inspected according to the production order. In this research, a mathematical programming model is developed for the economic modeling of sampling plans based on two evaluation criteria : the average outgoing quality(AOQ) and the average total inspection cost. An efficient solution procedure is then proposed using the functional structure of the two evaluation criteria and the procedure is numerically illustrated.

• Proceedings of The KACE
• /
• 2018.01a
• /
• pp.33-34
• /
• 2018

학업성취도를 결정짓는 중요한 변인 중 한 가지는 학습에 대해 학습자가 가지는 흥미이다. 따라서 보다 효과적인 로봇 프로그래밍 교육을 위해서는 학생이 로봇에 대해 가지는 흥미를 높여주는 것이 필요하다. 본 연구에서는 초등학생이 로봇에 대해 가지는 흥미를 향상시키기 위해 WeDo 2.0을 활용한 로봇 프로그래밍 교육을 실시한 후 효과를 검증하였다. 그 결과, WeDo 2.0을 활용한 로봇 프로그래밍 교육이 로봇 학습에 대한 흥미와 로봇 학습에 대한 자신감 향상에 효과가 있음을 알 수 있었다. 그러나 본 연구는 WeDo 2.0 활용 로봇 프로그래밍 교육을 실시한 집단만을 대상으로 하여 진행되었으므로 통제집단과의 비교를 통해 보다 정확한 변인을 조사하는 후속 연구가 진행될 필요가 있다.

• Journal of The Korean Association of Information Education
• /
• v.14 no.3
• /
• pp.385-393
• /
• 2010

Elementary information education is currently provided in accordance with the 2000 ICT educational guidelines. Although the focus of education has shifted from practical use to computer science since 2005, in which way academic education should be led isn't yet clear. The purpose of this study was to examine the impacts of computer science education(CS education) by an education programming tool on school children's awareness of that education. The selected students received education about unplugged, scratch and robot programming, part of the computer science curriculum, in 12 sessions. As a result, there were significant differences between the experimental and control groups in all the variables that included attitude to computer science, interest in that, satisfaction level, self-efficacy and perception of the value of CS education. The findings of the study suggested that in CS education, the improvement of thinking faculty should take precedence over practical use of what's learned, which is expected to heighten the value of that education.