• Education of Primary School Mathematics
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• v.21 no.2
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• pp.131-150
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• 2018

The structure of a mathematics task shapes the aspects of learning of those who solve the task. This study explores the process of understandings on the statistical variability of primary school students. Students were given two problems with different degrees of structuring - a well-structured problem (WSP) and an ill-structured problem (ISP) - and discussed in a group to solve each task. The highest level of development achieved in both cases appeared to be similar. However, when given the ISP, students dynamically proposed ideas and justified the conclusion based on their hypothesis. Furthermore, all students actively participated in solving the ISP until the end whereas some students were marginalized while solving the WSP. This discrepancy results from the difference in the degrees of task structuring.

• Journal of the Korean Institute of Intelligent Systems
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• v.25 no.6
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• pp.600-606
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• 2015

Applications of the drone have been enlarged and study on the quad-copter system has been widely progressed. Quad-copter system is raised vertically with four propellers, and it is free to move side to side, and upper and lower. It is also a typical example of non-linear systems. In this paper, we design two-input fuzzy logic control systems in order to control the quad-copter that is complex nonlinear system. And then we analyze their control rule tables and derive some characteristics that they present skew symmetric property and the control actions are enhanced as the distance from the diagonal band. This property enables the design of other control systems. We here design simple-structured fuzzy logic control systems and simulate them. We confirm some effects of the proposed systems and finally discuss about them.

• Journal of the Korean Ceramic Society
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• v.45 no.4
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• pp.226-231
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• 2008

The dense sintered bodies with >95% theoretical densities were successfully obtained from the $BaZrO_3,\;BaCeO_3,\;Ba(Zr_{0.7}Ce_{0.3})O_3$ solid solution, and core-shell structured $0.7BaZrO_3-0.3BaCeO_3$ composite powders prepared by sol-gel methods. The activation energy of $Ba(Zr_{0.7}Ce_{0.3})O_3$ solid solution calculated from the Arrhenius plot of the proton conductivities was similar to that of $BaZrO_3$. The activation energy of core-shell structured $0.7BaZrO_3-0.3BaCeO_3$ composite, however, was much lower than that of $BaZrO_3$ or $Ba(Zr_{0.7}Ce_{0.3})O_3$ solid solution, and was very similar to that $BaCeO_3$. These results could be assigned to the Ce-rich grain boundary which was clearly observed by EDX in core-shell structured $0.7BaZrO_3-0.3BaCeO_3$ composite.

• Journal of KIISE:Software and Applications
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• v.29 no.5
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• pp.319-325
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• 2002

Tracking moving objects is one of the most important techniques in motion analysis and understanding, and it has many difficult problems to solve. Especially, estimating and identifying moving objects, when the background and moving objects vary dynamically, are very difficult. It is possible under such a complex environment that targets may disappear totally or partially due to occlusion by other objects. The Kalman filter has been used to estimate motion information and use the information in predicting the appearance of targets in succeeding frames. In this paper, we propose another version of the Kalman filter, to be called structured Kalman filter, which can successfully work its role of estimating motion information under a deteriorating condition such as occlusion. Experimental results show that the suggested approach is very effective in estimating and tracking non-rigid moving objects reliably.

• Journal of the Korea institute for structural maintenance and inspection
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• v.21 no.3
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• pp.102-113
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• 2017

A new index for the buckling strength of non-structured plates is proposed. The external work or the deformation energy caused by the external loads or the boundary displacement controled by a load parameter is calculated along an equilibrium path of the member under consideration. If the second variation of the energy with respect to the parameter loses its positiveness, it defined as the limit of the stability. In contrast to the current method given in codes where the stability limit is evaluated by using only representative internal forces, the evaluation of the stability limit is always consistent even with the change of the distribution of the internal forces on the boundary. If the elasticity is concerned, the result from this proposed approach becomes identical to that from the classical methods.

• KSBB Journal
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• v.15 no.1
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• pp.88-95
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• 2000

We have produced new-structured oligosaccharides using immoobilized mixed-enzyme reactor of destransucrase from Leuconostoc mesenteroides B-512FMCM and $\alpha$-amylase from Aspergillus oryzae. The reactors of immobilized mixed-exzyme beads were more efficient for the production of oligosaccharides than that of each immobilized enzyme bead in stirred-tank reactior(STR) or in packed-bed reactor(PCR). In continuous flow reactor, the immobilized mixed-enzyme bead in PBR was more stable than in STR, and 52% of initial yield was maintained for 200 hr. New structured-oligosaccharides (NOS) reduced the change of pH in the culture of Streptococcus mutans. It also showed an inhibitory effect on the growth of Staphylococcus aureus.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.13 no.6
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• pp.145-159
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• 2010

A Sustainable Structured wetland Biotop (SSB) system was planned, designed, and finally constructed, and maintained in the An-teo Reservoir ecological park, which is the habitat of the endangered Gold-spotted Pond Frog. The system purifies polluted water of An-teo Reservoir which flows from up to bottom within the system. Water was sampled once a month at the inlet and at the outlet from December, 2009 to August, 2010. BOD5, SS, T-N and T-P were analyzed. Average influent and effluent BOD5 concentration was 2.9 and 1.0 mg/L, respectively, and BOD5 removal was 67%. SS concentration of influent and effluent averaged 18.1 mg/L and 2.5 mg/L, respectively, and SS abatement amounted to 86%. Average influent and effluent T-N concentration was 0.426 mg/L and 0.147 mg/L, respectively, and T-N retention was 66%. T-P concentration of influent and effluent averaged 0.071 mg/L and 0.022 mg/L, respectively, and T-P removal amounted to 68%. Plant and frog species of the system were monitored during the period. Amphibia and reptiles provided 7 species and 4 families including the Endangered Gold-Spotted Pond Frog (Rana chosenica ) which also lives in the system. Twenty-six plant species were naturally introduced into the system, however, they didn't make up a significant portion of the plant populations compared with the planted species. The endangered plants, Bladderwort (Utricularia vulgaris var. japonica ) and Euryale ferox were observed in An-teo Reservoir as well as in the system.

• The Transactions of the Korea Information Processing Society
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• v.6 no.12
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• pp.3514-3522
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• 1999

While the method of information collection and visual interface technique have been researched actively on web information retrieval, a study on structured modeling for effective classification of a wide collective information leaves to be desired. In this paper, we represent information feature based on structured information model. It aims at carrying out effectively the user's retrieval environment through visualization technique with analyzing the information feature. We propose a information classification method using Facet units and we construct the object model, table model, SQL code to define the relation of the information, and represent the information feature based on a wide range of views. After users gain a better global understanding of the information feature, retrieve more easily through their information. Conventional information retrieval is user-oriented to be what user want, but proposed technique it data-oriented which helps users to understand what exist in database by showing information feature.

• Nuclear Engineering and Technology
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• v.35 no.4
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• pp.318-335
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• 2003

Expert judgment is frequently employed in the search for the solution to various engineering and decision-making problems where relevant data is not sufficient or where there is little consensus as to the correct models to apply. When expert judgments are required to solve the underlying problem, our main concern is how to formally derive their technical expertise and their personal degree of familiarity about the related questions. Formal methods for gathering judgments from experts and assessing the effects of the judgments on the results of the analysis have been developed in a variety of ways. The most important interest of such methods is to establish the robustness of an expert's knowledge upon which the elicitation of judgments is made and an effective trace of the elicitation process as possible as one can. While the resultant expert judgments can remain to a large extent substantiated with formal elicitation methods, their applicability however is often limited due to restriction of available resources (e.g., time, budget, and number of qualified experts, etc) as well as a scope of the analysis. For this reason, many engineering and decision-making problems have not always performed with a formal/structured pattern, but rather relied on a pertinent transition of the formal process to the simplified approach. The purpose of this paper is (a) to address some insights into the balanced use of formally structured and simplified approaches for the explicit use of expert judgments under resource constraints and (b) to discuss related decision-theoretic issues.

• Journal of the Korean Society for Library and Information Science
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• v.49 no.3
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• pp.81-107
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• 2015

This study describes the Bottom-up method for implementation of an ontology system from the RDB. The STNet, a structured terminology glossary based on RDB, was served as a test bed for converting to RDF ontology, for generating the inference rules, and for evaluating the results of the semantic search. We have used protege editor of the ontology developing tool to design ontologies with test data. We also tested the designed ontology with the Inference Engine (Pellet) of protege editor. The generated reference rules were tested by TBox and SPARQL queries through STNet ontology. The results of test show that the generated reference rules were verified as true and STNet ontology were also evaluated to be useful for searching the complex combination of semantic relation.