• Journal of Educational Research in Mathematics
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• v.11 no.2
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• pp.385-402
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• 2001

The purpose of this study is to conceptualize 'proof' school mathematics. We based on the assumption the following. (a) There are several different roles of 'proof' : verification, explanation, systematization, discovery, communication (b) Accepted criteria for the validity and rigor of a mathematical 'proof' is decided by negotiation of school mathematics community. (c) There are dynamic relations between mathematical proof and empirical theory. We need to rethink the nature of mathematical proof and give appropriate consideration to the different types of proof related to the cognitive development of the notion of proof. 'proof' in school mathematics should be conceptualized in the broader, psychological sense of justification rather than in the narrow sense of deductive, formal proof 'proof' has not been taught in elementary mathematics, traditionally, Most students have had little exposure to the ideas of proof before the geometry. However, 'proof' cannot simply be taught in a single unit. Rather, proof must be a consistent part of students' mathematical experience in all grades, in all mathematics.

• Journal of the Korean Society of School Health
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• v.4 no.2
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• pp.146-158
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• 1991

There is no doubt that the school health education in school health services is the most important component. But the concept and scope of the school health education is still not recognized and accepted satisfactorily in Korea. It is generally accepted that health education is a process of changing of attitude and behavior forward health practice. The term attitude refers to certain regularities on the part of an individual in feelings, thoughts, and predispositions to act toward some aspect of his environment. Attitudes have three components: affective, cognitive, and behavioral. The strategies of attitude change in school health education consist of incentive, justification, and coersion. In this study I explained reinforcement and motivation as the strategies of attitude change. The attitude change is not built in a day. When the teachers give the pupils knowledge, comprehension, or skill through school health education proper to each stage, then the attitude change will be realized.

• Proceedings of the IEEK Conference
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• 2003.07e
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• pp.1711-1714
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• 2003

The noise in an image degrades image quality and deteriorates coding efficiency of compression. Recently, various edge-preserving noise filtering methods based on the nonstationary image model have been proposed to overcome this problem. In most conventional nonstationary image models, however, pixels are assumed to be uncorrelated to each other In order not to increase the computational burden too much. As a result, some detailed information is lost in the filtered results. In this paper, we propose a computationally feasible adaptive noise smoothing algorithm which considers the nonstationary correlation characteristics of images. We assume that an image has a nonstationary mean and can be segmented into subimages which have individually different stationary correlations. Taking advantage of the special structure of the covariance matrix that results from the proposed image model, we derive a computationally efficient FFT-based adaptive linear minimum mean square error filter. The justification for the proposed image model is presented and the effectiveness of the proposed algorithm is demonstrated experimentally.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2003.11a
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• pp.235-242
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• 2003

This reserch is to compare and analyze of the residence disposition and feature of ground plan on Seomi 2 Dong in An-dong and Hyun-ri in Mun-gyong. The scope of this reserch concentrated on 33-housed which are 12-housed in Seomi 2 Dong and 21-housed in Hyun-ri. The focus of this reserch is mainly to investigate the characteristic of the site, and ground plans on individual houses. As result of it, there are mostly Yeo-Kan houses (six spans sized) on Seomi 2-dong village in An-Dong on the other hand there are a lot of Straight-Houses in Hyun-ri in Mun-gyong. Otherwise in characteristic of residence, There is dissimilarity between Seomi 2-dong which located in mountainous districts has space organization of utilitarian and Hyun-Ri has justification primacy as a farm village.

• Computers and Concrete
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• v.12 no.1
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• pp.37-51
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• 2013

The responses of reinforced concrete slabs subject to an impact loading near the ultimate load range are explored. The analysis is carried out on a simply supported rectangular reinforced concrete slab using a nonlinear explicit dynamic procedure and considering three material models: Drucker-Prager, modified Drucker-Prager, and concrete damaged plasticity, available in the commercial finite element software, ABAQUS/Explicit. For comparison purposes, the impact force-time response, steel reinforcement failure, and concrete perforation pattern are verified against the existing experimental results. Also, the effectiveness of mesh density and damage wave propagation are studied independently. It is shown that the presently adopted finite element procedure is able to simulate and predict fairly accurate the behavior of reinforced concrete slab under impact load. More detailed investigations are however demanded for the justification of effects coming from an imperfect projectile orientation as well as the load and structural surface conditions, including the impulsive contacted state, which are inevitable in an actual impact environment.

• Journal of computational fluids engineering
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• v.19 no.2
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• pp.30-39
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• 2014

We report in this paper the analysis of the motion of a needle and a spring in a viscous fluid under the influence of gravitational force. Lateral shift as well as vertical motion of a needle falling in a viscous fluid has been observed from a simple experiment. We also observed the combined rotation and translation of a falling spring. The trajectory and velocity of the falling needle and the spring were obtained by using an image processing technique. We also conducted numerical simulation for both problems. For the falling-needle problem, we employed a theory; but it turns out that significant correction is required for the solutions to match the numerical and experimental data. For the falling spring problem various theoretical formula were tested for their justification, but none of the existing theories can successfully predict the numerical and experimental results.

• Journal of Korean Library and Information Science Society
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• v.42 no.2
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• pp.5-28
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• 2011

The ultimate mission of the university library is to provide the various information services in support of the teaching, research, and public service missions of the university. The achievement of the mission requires the optimal development and timely revision of university library standard that can be used as an operating guidelines and assessment tools. On the basis of this justification, this study has compared the trend and feature of library standards in major countries(USA, Canada, UK, Japan, Taiwan), analysed the problems and limitations of legal and recommended standards in Korea, and suggested the revised plan of Korean university library standard focusing on collections, staffs, and facilities.

• Journal of Korea Multimedia Society
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• v.23 no.4
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• pp.595-602
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• 2020

We propose a generative probabilistic model with Dirichlet prior distribution for topic modeling and text similarity analysis. It assigns a topic and calculates text correlation between documents within a corpus. It also provides posterior probabilities that are assigned to each topic of a document based on the prior distribution in the corpus. We then present a Gibbs sampling algorithm for inference about the posterior distribution and compute text correlation among 50 abstracts from the papers published by IEEE. We also conduct a supervised learning to set a benchmark that justifies the performance of the LDA (Latent Dirichlet Allocation). The experiments show that the accuracy for topic assignment to a certain document is 76% for LDA. The results for supervised learning show the accuracy of 61%, the precision of 93% and the f1-score of 96%. A discussion for experimental results indicates a thorough justification based on probabilities, distributions, evaluation metrics and correlation coefficients with respect to topic assignment.

• Journal of Advanced Marine Engineering and Technology
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• v.39 no.10
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• pp.1049-1053
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• 2015

This paper proposes to include engine information in Maritime Service Portfolio (MSP) for effective implementation of e-Navigation. Even though engine information is one of most important element to e-Navigation, MSP consists of mainly about navigation and communication information not included engine information. Furthermore, in reality, engine information sent from ship side such as mainly noon report and Planned Maintenance System (PMS) is too limited to make e-Navigation possibly. Therefore, Remote diagnostic structure receiving and sending data of engine information must be included in MSP for implementation of e-Navigation. Also, it has to be designed, and developed by Software Quality Assurance (SQA).

• Proceedings of the KIPE Conference
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• 2003.11a
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• pp.6-10
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• 2003

The reliability of power electronics system is very important In industrial, commercial and military applications. This paper presents the principles for NPC inverter as an available technology for the design and implementation of adaptive fault tolerant systems. The fault tolerance is obtained by the use of the particular construction. The control method is proposed to get the sinusoidal load current with constant amplitude. The strategy described in this paper is expected to provide an economic alternative to more expensive redundancy techniques which find justification only in a few specialized application.