• Journal of The Korean Association of Information Education
• /
• v.14 no.1
• /
• pp.123-130
• /
• 2010

In this paper, we introduce a new programming learning system for young students. The programming learning system consists of a LED display kit and a web-based flowchart system. The LED display kit acts as an output device by way of displaying lights while following a set of instructions given through a flowchart programming. In the flowchart system, the students use symbolic variables for the calculation and can get various displays or animations after creating a flowchart by drag-and-drop. Then we describe the survey results of various programming classes using our system between fall 2005 and spring 2009. The programming teaching was conducted with diverse groups such as elementary school students, gifted students, college students, and teachers etc. The responses from our in class surveys were generally positive.

• Child Health Nursing Research
• /
• v.6 no.3
• /
• pp.354-361
• /
• 2000

The purpose of this study was to examine the stressors and coping styles between headache- suffering children and headache-free children. The subjects of this study consisted of 112 headache-suffering children and 203 headache- free children. They were 5th and 6th grade of elementary school around Taegu city. The periods of study was from June 1, to July 20, 2000. Data were analyzed by SAS computer programme The results of this study were as follows: 1. The score of stressor of headache-suffering children was higher than that of headache- free children significantly. The scores of school stressor and mess media stressor of headache-suffering children were higher than those of headache-free children significantly. 2. There was no significant difference even though the mean score of the coping style in headache-suffering children was higher than that of headache-free children. There were also no significant differences in both problem-oriented coping style and emotion- oriented coping style. 3. Logistic regression analysis(stepwise) revealed that the most powerful predictor was the variable stressor in school(standardized estimate=0.316, P<.001), followed by stressor in mass media(standardized estimate=0.224, P<.05).

• The Journal of the Korea institute of electronic communication sciences
• /
• v.2 no.2
• /
• pp.67-74
• /
• 2007

Chattering phenomenon is still a large drawback of VSS. To overcome this problem, various approaches have been reported. A new notion of sliding sector has been proposed recently. Inside this sector, a kind of norm of the state decreases without control input. Therefore, so long as the state is constrained inside this sector, the norm of the state approaches to zero. The sliding sector theory is elementary study step and is studied about only linear systems. In this paper, new methods of the tracking control of unstable nonlinear systems using the sliding sector is proposed. This paper analyzes the stability, using Lyapunov function on the sliding sector. Through the computer simulations for an inverted pendulum system, it is verified that sliding sector control is capable to reduce the chattering.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.8 no.4
• /
• pp.807-814
• /
• 2004

Chattering phenomenon is still a large drawback of VSS. To overcome this problem, various approaches have been reported. A new notion of sliding sector has been proposed recently. Inside this sector, a kind of norm of the state decreases without control input. Therefore, so long as the state is constrained inside this sector, the norm of the state approaches to zero. The sliding sector theory is elementary study step and is studied about only linear systems. In this paper, new methods of stabilizing unstable nonlinear systems using the sliding sector is proposed. This paper analyzes the stability, using Lyapunov function on the sliding sector. Through the computer simulations for an inverted pendulum system, it is verified that sliding sector control is capable to reduce the chattering.

• Education of Primary School Mathematics
• /
• v.18 no.3
• /
• pp.217-234
• /
• 2015

Computer technology and internet environment have been adapted to teaching and learning in Korean educational context. However, there are several problematic areas in operating web site for teaching and learning mathematics. This study aims to investigate the operating system, such as designing web site, contents information, and contents connection of NRICH web site that has been operated as a part of 'Millennium Mathematics Project' of Cambridge University since 1997. Based on these categories, this study also gives the implications for how to develop theme-centered contents, accumulation of continuous and long-term data, induction of user's participation, and various cooperation project.

• Journal of Information Processing Systems
• /
• v.13 no.5
• /
• pp.1103-1125
• /
• 2017

This paper aims to extract an ObjectProperty-UsageMethod relation, in particular the HerbalMedicinalProperty-UsageMethod relation of the herb-plant object, as a semantic relation between two related sets, a herbal-medicinal-property concept set and a usage-method concept set from several web documents. This HerbalMedicinalProperty-UsageMethod relation benefits people by providing an alternative treatment/solution knowledge to health problems. The research includes three main problems: how to determine EDU (where EDU is an elementary discourse unit or a simple sentence/clause) with a medicinal-property/usage-method concept; how to determine the usage-method boundary; and how to determine the HerbalMedicinalProperty-UsageMethod relation between the two related sets. We propose using N-Word-Co on the verb phrase with the medicinal-property/usage-method concept to solve the first and second problems where the N-Word-Co size is determined by the learning of maximum entropy, support vector machine, and naïve Bayes. We also apply naïve Bayes to solve the third problem of determining the HerbalMedicinalProperty-UsageMethod relation with N-Word-Co elements as features. The research results can provide high precision in the HerbalMedicinalProperty-UsageMethod relation extraction.

• Journal of Information Technology Applications and Management
• /
• v.28 no.4
• /
• pp.13-20
• /
• 2021

In this paper, I was applied the life distribution following linear failure rate distribution, Lindley distribution and Burr-Hatke exponential distribution extensively used in the arena of software reliability and were associated the reliability possessions of the software using the nonhomogeneous Poisson process with finite failure. Furthermore, the average value functions of the life distribution are non-increasing form. Case of the linear failure rate distribution (exponential distribution) than other models, the smaller the estimated value estimation error in comparison with the true value. In terms of accuracy, since Burr-Hatke exponential distribution and exponential distribution model in the linear failure rate distribution have small mean square error values, Burr-Hatke exponential distribution and exponential distribution models were stared as the well-organized model. Also, the linear failure rate distribution (exponential distribution) and Burr-Hatke exponential distribution model, which can be viewed as an effectual model in terms of goodness-of-fit because the larger assessed value of the coefficient of determination than other models. Through this study, software workers can use the design of mean square error, mean value function as a elementary recommendation for discovering software failures.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.14 no.4
• /
• pp.769-774
• /
• 2019

The development of information technology in a software-centered society as of today is a very important, and the training of software utilizing robots has become popular in recent years. This study proposes efficient SW convergence education by providing curriculum and contents for science + SW convergence education in conjunction with instruction block coding program. It also complements the limitations of existing unstructured chemistry experiment teaching aid, We have developed a 'chemical experiment paradigm' that integrates software education that can be linked with other classes.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.13 no.2
• /
• pp.978-1002
• /
• 2019

With the rapid development of the Internet of Things, the problem of privacy protection has been paid great attention. Recently, Nikooghadam et al. pointed out that Kumari et al.'s protocol can neither resist off-line guessing attack nor preserve user anonymity. Moreover, the authors also proposed an authentication supportive session initial protocol, claiming to resist various vulnerability attacks. Unfortunately, this paper proves that the authentication protocols of Kumari et al. and Nikooghadam et al. have neither the ability to preserve perfect forward secrecy nor the ability to resist key-compromise impersonation attack. In order to remedy such flaws in their protocols, we design a lightweight authentication protocol using elliptic curve cryptography. By way of informal security analysis, it is shown that the proposed protocol can both resist a variety of attacks and provide more security. Afterward, it is also proved that the protocol is resistant against active and passive attacks under Dolev-Yao model by means of Burrows-Abadi-Needham logic (BAN-Logic), and fulfills mutual authentication using Automated Validation of Internet Security Protocols and Applications (AVISPA) software. Subsequently, we compare the protocol with the related scheme in terms of computational complexity and security. The comparative analytics witness that the proposed protocol is more suitable for practical application scenarios.

• Journal of The Korean Association of Information Education
• /
• v.26 no.5
• /
• pp.295-305
• /
• 2022

In the modern artificial intelligence society, the goal of education is to cultivate convergent talents who can adapt well to and lead the artificial intelligence society. The core competency required of convergent future talents is to be able to understand and create software well. In this respect, algorithmic education is very important. Therefore, in this study, an algorithm education program was developed to improve convergent thinking ability. The effectiveness was verified through the paired samples t-test by conducting a pre-post test of convergent thinking ability, and it was found that students' convergent thinking ability was significantly improved in the areas of algorithm knowledge and function.