• Journal of the Korean Society of Earth Science Education
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• v.15 no.2
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• pp.285-298
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• 2022

This study is to investigate the effects and characteristics of science and engineering integrated lessons on elementary students' creative engineering problem solving propensity (CEPSP). The science and engineering integrated lessons used in this study was a 10 lesson-hours STEM program, co-developed by University of Minnesota and Purdue University. The program was implemented in the 6th grade science class of H Elementary School located in P Metropolitan city. The main data of this study are the pre-post CEPSP result and interview with 5 students collected before and after the research. The CEPSP result was analyzed by a paired-sample t-test and hierarchical cluster analysis. As a result of the t-test, it was found that overall, the program has a positive effect on the students' CEPSP score. As a result of cluster analysis, it was confirmed that studnets' CEPSP could be classified into two groups (lower and higher score cluster). Five students whose, CEPSP score has significantly improved after the lessons were interviewed to find out what the characteristics of the program that contribute the significant change are. As a result of conducting centroid analysis of the interview transcription and the hybrid analysis method, it was found that the meaningful experiences that the five students commonly shared were 'problem solving through collaboration' and 'through repeated experiments (redesign)', problem solving' and 'utilization of scientific knowledge'. As minor reactions, 'choice of the best experimental method' and 'difference between science and engineering' appeared.

• Journal of Science Education
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• v.33 no.2
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• pp.193-206
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• 2009

The purpose of this study was to examine the effect of the consistent presentation of illustrations about the aligning direction of the Axis on the middle school students' acquisition and retention of astronomical concepts. This study was taken using the nonequivalent control-group pretest-posttest design on 116 7th middle school subjects. The same teaching and learning activities were given to both the experimental (n=59) and control groups (n=57) through three lessons. The experimental group was given a consistent presentation of the illustrations about the aligning direction of the Axis, while the control group was given an inconsistent presentation of the same illustrations about aligning direction. Two days after the three lessons, the 1st posttest was administered to compare the statistical difference of mean of both groups, using ANCOVA test. The result of ANCOVA test implicated that the consistent presentation of the illustrations about the aligning direction of the Axis had a positive influence on the experimental group's acquisition of the concepts. The 2nd posttest result for retention effect was given two month later by one-paired t-Test in each group and showed that the method had a positive effect on the experimental group, compared with control group. The results of this study implicated that paying careful attention to using the consistent illustration is highly beneficial for students' meaningful learning on astronomical concepts.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.28 no.1
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• pp.145-153
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• 2018

SSL (Secure Socket Layer) and TLS (Transport Layer Security) are widely used protocols for secure and encrypted communication over a computer network. However, there have been reported several security vulnerabilities of SSL/TLS over the years. The vulnerabilities can let an adversary carry out critical attacks on SSL/TLS enabled servers. In this paper, we have developed a system which can periodically scan SSL/TLS vulnerabilities on internal network servers and quickly detects, reports and visualizes the vulnerabilities. We have evaluated the system on working servers of Naver services and analyzed detected vulnerabilities. 816 vulnerabilities are found on 213 internal server domains (4.2 vulnerabilities on average) and most vulnerable servers are not opened to public. However, 46 server domains have old vulnerabilites which were found 2016. We could patch and response to SSL/TLS vulnerabilites of servers by leveraging the proposed system.

• Journal of The Korean Association of Information Education
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• v.24 no.6
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• pp.551-562
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• 2020

The purpose of this study is to investigate the effects of Data Science Education classes using PBL-based App Inventor on elementary student Computational Thinking and Creativity. Based on the results of the pre-requisite analysis by Rossett's demand analysis model, PBL-based Data Science Education class was designed according to the procedure of ADDIE model which is 42 hours of classroom instruction for elementary student. As a result of the Paired t-test, it was proved that the Computational Thinking was statistically significantly improved in the post-test. In addition, as a result of the Paired t-test and Wilcoxon's signed rank test, it was found that the sub-factors of Creativity were 'Originality', 'Fluency', 'Closure', 'Average', and 'Index'. Therefore, it was confirmed that the PBL-based Data Science Education class using App Inventor is effective in improving Computational Thinking and Creativity of elementary student.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2017.04a
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• pp.149-149
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• 2017

본 논문은 생산라인 자동화를 위한 로봇으로 제조업 시장 확대에 가장 큰 걸림돌이 되는 가격 경쟁력 및 인력난 해소를 위해 설계하였으며 다양한 소재에 대응하기 위해 그리퍼를 교체하여 적용이 되도록 하였다. 자동화를 위한 로봇은 소재의 내외경 가공 및 검사까지 모든 공정이 일괄적으로 이루어 져야하며 LCD 모니터에 생산수량 및 불량률 등의 정보를 실시간으로 나타내어 효율적인 생산계획을 수립할 수 있도록 하였다. 생산라인 자동화를 위해 로봇의 설계는 Auto CAD를 이용하였다. 부품의 가공은 CNC에 적용하기 위해 자동공급장치를 설계하였다. 가공이 완료된 후 측정한 값을 LCD모니터를 통하여 작업자가 알아볼 수 있게 나타냈다. 외경 1은 40.405, 외경2는 32.201, 내경 1은 23.346, 내경 2는 34.302로 나타났다. 측정결과 불량 측정을 위해 측정부의 결과 값이 나타나며 불량이 발생하면 그래프를 이용하여 어떤 부위에서 발생했는지를 알 수 있도록 하였다. 또한 결과 값은 자동으로 저장되도록 하였다. 생산라인 자동화를 위해 100EA를 측정한 결과 외경 1은 40.40438, 외경2는 32.20164, 내경 1은 23.34830 내경 2는 34.30033의 평균값을 나타냈다. 측정값의 검증은 하이트게이지로 측정한 결과 0.003 이내의 결과를 나타냈다. 따라서 본 로봇 자동화 시스템을 적용한다면 생산성 향상 및 불량률 감소가 가능하여 인력대체 및 가격경쟁력이 가능하다고 판단된다.

• 재활복지
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• v.22 no.2
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• pp.103-126
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• 2018

The purpose of this study is to examine the effect of the disability awareness program and to search for its development plan. For this, the disability awareness program was developed and lecturers were educated. And it had been exercised and examined its effect to 508 people including elementary, middle and high school students and adults nationwide from June to October in 2017. To examine the effect of the program, Disability Awareness Index developed by Korean Foundation for Persons with Disabilities was used. It was also examined on the change of the disability awareness(understanding disability and human rights of disabled) and of the knowledge about discrimination and differentiation. Pre-post tests based on the experimental design were performed and data were analyzed using descriptive statistics, paired t-test, independent t-test and ANOVA. The research results showed as follows; Disability awareness was improved significantly and knowledge about discrimination and differentiation were enhanced after attending the program. Also, it was found that the factors like gender, age, and program types made significant difference to the effects of the program. Based on the research results, this study suggested for the development disability awareness program and the directions for future studies.

• Proceedings of the Korean Information Science Society Conference
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• 2007.06c
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• pp.38-42
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• 2007

최근 원전 경보시스템은 운전원이 상황을 판단하는 데 불필요한 일시적인 경보나 결과 경보를 감축 및 억제하여 운전원의 주의가 특별히 필요한 경보에 집중하도록 하는 개량형 경보처리를 필요로 한다. 데이터베이스를 기반으로 원전 개량형 경보 시스템은 데이터베이스에 어떤 이벤트가 발생하면, 특정 공정을 검사해 조건이 맞는 경우 어떤 행동을 자동적으로 수행하여 경보처리를 수행할 필요가 있다. 또한 능동규칙의 사용으로 데이터베이스 상태 변화에 자동으로 대응하는 유용성을 확보해야 한다. 따라서 시간제한 개념을 가지는 데이터베이스 모델과 이를 바탕으로 한 능동 처리 기능을 가진 실시간 시스템을 구축하여 경보감축 및 억제를 수행할 수 있다. 본 논문은 원전의 개량형 경보처리를 위한 데이터베이스 설계 고려 사항들을 분석하여 실시간 능동 데이터베이스 기술을 도입하기 위한 분석을 수행한다. 그리고 능동 규칙을 이용한 개량형 경보처리 예와 구현 고려사항을 파악한 후 개발 계획을 정립한다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.41 no.9
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• pp.1103-1107
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• 2016

Network assets have been protected from malware infection by checking the integrity of mobile devices through network access control systems, vaccines, or mobile device management. However, most of existing systems apply a uniform security policy to all users, and allow even infected mobile devices to log into the network inside for completion of the integrity checking, which makes it possible that the infected devices behave maliciously inside the network. Therefore, this paper proposes a network defense mechanism based on isolated networks. In the proposed mechanism, every mobile device go through the integrity check system implemented in an isolated network, and can get the network access only if it has been validated successfully.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.18 no.2
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• pp.75-84
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• 2008

Recently, the straightforward CRT-RSA was shown to be broken by fault attacks through many experimental results. In this paper, we analyze the fault attacks against CRT-RSA and their countermeasures, and then propose a new fault infective method resistant to the various fault attacks on CRT-RSA. In our CRT-RSA algorithm, if an error is injected in exponentiation with modulo p or q, then the error is spreaded by fault infective computation in CRT recombination operation. Our countermeasure doesn't have extra error detection procedure based on decision tests and doesn't use public parameter such as e. Also, the computational cost is effective compared to the previous secure countermeasures.

• Journal of the Korean Society of Earth Science Education
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• v.12 no.3
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• pp.291-301
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• 2019

The purpose of this study is to develop HTE-STEAM program using natural disasters for high school students and to verify their attitude and satisfaction with STEAM. We developed the HTE-STEAM program utilizing natural disasters and tested the effectiveness of 243 students from G High School and N High School. For data analysis, a single group pretest and post response t-test were conducted to verify the effects on attitudes and satisfaction with STEAM. The research results are as follows. First, we developed STEAM education programs for high school students by selecting the topic of "natural disasters" in the area of earth science and flying drones as lifesaving drones. The six-hour program was designed to give students the experience to solve problems by applying essential knowledge related to natural disasters and drones, and what they learned in other situations. Second, there was a significant statistical test result in the t-test of the corresponding sample by the difference between the pre and post score of the STEAM attitude test (p <.05). The drone-based HTE-STEAM program had a significant improvement in the overall attitude toward STEAM education, which consists of seven subfactors. Third, in the HTE-STEAM satisfaction test, the average value of the lower job offer was 3.64 ~ 3.76, which showed a positive response overall. It is judged that the students' satisfaction is improved through the students' understanding of the problem situation and the design of creative convergence and production process.