• The KIPS Transactions:PartD
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• v.12D no.3 s.99
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• pp.335-344
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• 2005

Recently open data mining methods focusing on a data stream that is a massive unbounded sequence of data elements continuously generated at a rapid rate are proposed actively. Knowledge embedded in a data stream is likely to be changed over time. Therefore, identifying the recent change of the knowledge quickly can provide valuable information for the analysis of the data stream. This paper proposes a sliding window technique for finding recently frequent itemsets, which is applied efficiently in open data mining. In the proposed technique, its memory usage is kept in a small space by delayed-insertion and pruning operations, and its mining result can be found in a short time since the data elements within its target range are not traversed repeatedly. Moreover, the proposed technique focused in the recent data elements, so that it can catch out the recent change of the data stream.

• Proceedings of the Korea Technology Innovation Society Conference
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• 2017.11a
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• pp.1551-1564
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• 2017

지속가능발전목표(SDGs)를 달성하기 위해 국제 사회는 녹색기술 관련 R&D와 산업에 적극적인 투자와 인프라 육성에 노력을 경주하고 있다. 이러한 국제적 노력에 발맞추어 우리나라도 경제 및 환경의 조화와 균형 성장을 위해 녹색기술 R&D에 대한 투자를 지속적으로 확대하고 있다. 본 논문에서는 NTIS의 '녹색기술분야분류'를 가지고 최근 국가연구개발사업의 녹색기술 관련 투자현황에 대한 분석을 수행하고 최근 2013~2016년의 총 213,618개 과제 중 녹색기술 36,490개 과제의 키워드 분석을 통해 집중연구 분야 및 융합연구 분야를 탐색한다. 녹색기술 상위 키워드는 '기후변화', '친환경', '태양전지', '고효율', '연료전지', '이산화탄소, '그래핀', '바이오매스' 순으로 나타났다.

• The Journal of the Korea Contents Association
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• v.22 no.8
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• pp.159-169
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• 2022

The study explored the key factors(content satisfaction factor, functional satisfaction factor, inertia factor and situational factor) that influence OTT users' continued use from the perspective of Behavioral Economics. In addition to rational factors that make OTT users feel satisfied after experiencing the contents and functions by the platform, we assumed that it would also affect habitual factors from the 'status quo bias'. To verify this, an online survey was conducted on 523 adults in 20s and 40s who have subscribed to the Top3 OTT platform(Netflix, Wavve, and Tving). As a result of regression analysis, 'content satisfaction factor', 'functional satisfaction factor' and 'inertia factor' were significant in OTT continued use. 'Inertia factor' did not affect domestic OTT users. Unlike previous studies that supposed OTT service users as beings with complete rationality, this study is meaningful to explain OTT continued use by applying 'bounded rationality'.

• The Journal of the Korea Contents Association
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• v.19 no.10
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• pp.372-384
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• 2019

The purpose of this study was to investigate the meaning of the extracurricular activities in the early childhood education institutions because the discussions and the discrepancy between theoretical viewpoint and reality are gradually expanded. For this purpose, the classes of three early childhood education institutes were observed, and interviews with the instructors were conducted where extracurricular activities programs were implemented. The meanings of extracurricular activities in the early childhood education institutes were 'coexistence of newness and pleasure', 'meaning as learning', 'diverse teaching media experience' and 'inevitable limit' in the reality of formal lessons and other situations. Based on the results of this study, it is necessary to make comprehensive and complementary approaches between the formal curriculum and extracurricular activities for the future high quality extracurricular activity education. Continuous training and education of the instructor are required for better extracurricular activities.

• Proceedings of the Korea Technology Innovation Society Conference
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• 2002.05b
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• pp.71-91
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• 2002

본 연구의 목적은 산학협력의 일환으로 진행된 RRC 연구과제가 성과로 연결되기 위한 필요요인이 무엇인지를 밝히는 연구이다. 이를 위해 3년간 수행된 67건의 과제를 중심으로 연구책임자와 참여업체를 연구대상으로 조사하였다. 본 논문에서는 산학협력에 대한 이론적 고찰 후, 연구과제의 도출과정과 운영과정을 기술한 뒤, 성과가 높은 집단과 낮은 집단의 주요 차원별 구성형태(configuration)를 살펴보았다. 본 연구의 성격은 이론 검증적 연구가 아닌 이론 도출적 연구이며, 이중 탐색적 단계에 해당된다. 연구결과를 살펴보면, 과제제안의 경우 연구책임자 단독보다 업체의 참여가 중요하며, 이는 차후 과제활용도를 높이고 경쟁력제고에 도움이 된다. 또한 운영상 개선할 사항으로 연구부문에서는 연구성과의 응용보완, 산학협동에서는 소재분야의 수요조사와 미래형 소재산업 방향 제시 등이 있으며, 인력양성에서는 배출된 인력의 재교육과 연구원의 산업체 연수강화 등이 제시되었다. 개발 후 일관 기술이전보다 개발과정 중 참여 업체 연구원 참여를 통한 단계적 이전이 더욱 효과적인 것으로 나타났다. 한편 성공적인 집단과 그렇지 못한 집단의 구성형태를 살펴보았으며, 이 두 집단을 판별하는 중요한 변수로는 과제 선정시 개발가능성과 기술이전 후의 지속적 기술지원의 고려정도가 있으며, 참여기업의 혜택면에서 기술특허 활용정도와 기술관련 애로 사항 해결여부가 중요한 변수로 나타났다.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.47 no.3
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• pp.187-194
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• 2019

The off-axis Infra-Red(IR) seeker is mounted on the nose cone side of the anti-air high speed missile to alleviate thermal shield effect due to aerodynamic heating. The seeker output can not be regarded as the Line-of-Sight(LOS) rate any more as missile's roll motion to keep the target tracking is associated. In this paper, we propose a method to calculate the LOS rate for off-axis seeker on a 2-axis gimbal. Firstly, true LOS rate equations are analytically derived but not implementable because boresight error rate is not measurable. And then the first order lag approximation to obtain boresight error rate is proposed. The proposed LOS rate calculation method can compensate the coupling effect by considering the rotations of missile and gimbal. The performance of the proposed method is verified via full nonlinear 6-DOF(Degree of Freedom) simulations.

• Journal of Korea Water Resources Association
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• v.47 no.4
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• pp.357-370
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• 2014

This study aims to develop a rainfall field tracking method for depth-area-duration (DAD) analysis and assess whether the proposed tracking methods are able to properly estimate the maximum average areal rainfall (MAAR) within the study area during a rainfall period. We proposed three different rainfall field tracking algorithms (Box-tracking, Point-tracking, Advanced point-tracking) and then applied them to the virtual rainfall field with 1hr duration and also compared DAD curves of each method. In addition, we applied the three tracking methods and a traditional GIS-based tool to the typhoon 'Nari' rainfall event of the Yongdam-Dam watershed and then assess applicability of the proposed methods for DAD analysis. The results showed that Box-tracking was much faster than the other two tracking methods in terms of searching for the MAAR but it was impossible to describe rainfall spatial pattern during its tracking processes. On the other hand, both Point-tracking and Advanced point-tracking provided the MAAR by considering the spatial distribution of rainfall fields. In particular, Advanced point-tracking estimated the MAAR more accurately than Point-tracking in the virtual rainfall field, which has two rainfall centers with similar depths. The proposed automatic rainfall field tracking methods can be used as effective tools to analyze DAD relationship and also calculate areal reduction factor.

• Journal of Korea Society of Industrial Information Systems
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• v.20 no.5
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• pp.95-105
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• 2015

Prior studies have reported equivocal patterns of the results about the relationships between family involvement and firm performance, particularly financial performance. In line with this research trend, this study focuses on non-financial performance that agency costs may marginally influence. tries to identify the relationship between nepotism and the three types of innovation performance, namely corporate entrepreneurship, radical innovation performance, and incremental innovation performance. The results has shown that family involvement is positively correlated with the three types of innovation performance.

• The Mathematical Education
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• v.61 no.4
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• pp.631-651
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• 2022

It has been alerted that Korean students' mathematical affective achievement is very low. In order to solve this problem, various policies related to mathematical affective domains have been promoted, but it is necessary to examine various existing policies and explore the direction for improving them in more essential aspects. Based on previous studies that the growth mindset helps to increase students' affective achievement, this study focused on improving students' math-related growth mindset and ultimately exploring policies that can increase mathematical affective achievement. Therefore, the current status of mathematical affective achievement of Korean students was examined, and the policies and related cases in the mathematical affective domain were investigated. Based on the results, some keywords were derived and then the directions of policy for improving the math-related growth mindset and the affective achievement of students were suggested.

• Journal for History of Mathematics
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• v.26 no.1
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• pp.103-118
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• 2013

The purposes of this article are to discuss how mathematics classroom in the departmentalized classroom system can be established for effective education, and describe current efforts within departmentalized mathematics classrooms toward achieving this goal. A departmentalized mathematics classroom would be most effective in improving education if implemented after comprehensive preplan for the specificity of the subject and characteristics of students depending on their grades and levels in their unique school environment. Continued investigation for effective communication of teaching and learning methods in a mathematics classroom will be a key component to set a departmentalized mathematics classroom up and to improve the quality of education.