• Journal for History of Mathematics
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• v.22 no.3
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• pp.153-170
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• 2009

Zoltan, P. Dienes is a famous researcher and practitioner who has tried to teach mathematical structures to children for about 50 years. Even though his ideas of teaching mathematics and materials including MAB have been well known in Korea, they are only a part of his achievement he has developed for his whole life. So this article is designed for taking an overview of his whole life and achievement and getting some implications for today's mathematics education. In this article, his life story could be divided by five periods in terms of a scholastic career and his research achievement could be reorganized with respect to five theses: psychology of learning mathematics, mathematical curriculum, teacher education, games and material for mathematical learning. As a result, it is found that there is a deep connection between his personal life and his scholastic career.

• Korean Journal Plant Pathology
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• v.1 no.3
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• pp.184-189
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• 1985

Transmission of mulberry dwarf mycoplasma (MDM) from diseased mulberry to 5 herbaceous plants (periwinkle, white clover, Ladino clover, red clover, and Chinese milk vetch) through insect vector, Hishimonus sellatus, was confirmed by symptom expression and microscopic evidences. The earliest symptom appearance was noticed on periwinkle in which incubation period was 25-30 days, while it ranged 35-40 days in the other plant species. The common symptoms of MDM infected plants were characterized by poor plant growth with accompanying discolorations of leaves (chlorosis with vein clearing in periwinkle, reddish in red clover, brownish in white and Ladino clovers, and yellowish in Chinese milk vetch). Mycoplasmal infections were diagnosed light microscopically by Dienes' and toluidine blue staining of hand-cut and Epon-embedded sections, respectively. In Dienes' stain, all the plants infected with MDM showed specific staining reaction in phloems. In toluidine blue stain, mycoplasmal existence was noted by granular appearance in sieve tubes which were confirmed to be mycoplasma-like organisms under an electron microscope.

• Journal of Elementary Mathematics Education in Korea
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• v.17 no.1
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• pp.165-184
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• 2013

In order to utilize Sphinx Puzzle in shape education or deductive reasoning, a lesson employing Dienes' six-stage theory of learning mathematics was structured to be applied to students of 6th grade of elementary school. 4 students of 6th grade of elementary school, the researcher's current workplace, were selected as subjects. The academic achievement level of 4 subjects range across top to medium, who are generally enthusiastic and hardworking in learning activities. During the 3 lessons, the researcher played role as the guide and observer, recorded observation, collected activity sheet written by subjects, presentation materials, essays on the experience, interview data, and analyzed them to the detail. A task of finding every possible triangle out of pieces of Sphinx Puzzle was given, and until 6 steps of formalization was set, students' attitude to find a better way of mathematical deduction, especially that of operational thinking and deductive thinking, was carefully observed and analyzed.

• The Journal of the Korea Contents Association
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• v.11 no.3
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• pp.73-83
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• 2011

The question answering system shows the answers that are input by other users for user's question. In spite of many researches to try to enhance the satisfaction level of answers for user question, there is a essential limitation. So, the question answering system provides users with the method of recommendation of another questions that can satisfy user's intention with high probability as an auxiliary function. The method using the fuzzy relational product operator was proposed for recommending the questions that can includes largely the contents of the user's question. The fuzzy relational product operator is composed of the Kleene-Dienes operator to measure the implication degree by contents between two questions. However, Kleene-Dienes operator is not fit to be the right operator for finding a question answers pair that semantically includes a user question, because it was not designed for the purpose of finding the degree of semantic inclusion between two documents. We present a novel fuzzy implication operator that is designed for the purpose of finding question answer pairs by considering implication relation. The new operator calculates a degree that the question semantically implies the other question. We show the experimental results that the probability that users are satisfied with the searched results is increased when the proposed operator is used for recommending of question answering system.

• Bulletin of the Korean Chemical Society
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• v.31 no.3
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• pp.559-560
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• 2010

• Bulletin of the Korean Chemical Society
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• v.30 no.2
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• pp.471-474
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• 2009

• Bulletin of the Korean Chemical Society
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• v.25 no.10
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• pp.1463-1464
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• 2004

• Journal of the Korean Chemical Society
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• v.23 no.5
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• pp.286-295
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• 1979

In order to predict the effect of Lewis acid catalysis on the regioselectivity of the Diels-Alder reactions between unsymmetrically substituted dienes and dienophiles, the frontier orbital theory applied to the theoretical model of the Lewis acid complexed dienophile was studied by means of CNDO/2 MO. In the majority of reactions, CNDO/2 calculations gave good results in accordance with experimental orientation. Also, it was shown that the secondary orbital interaction played an important role in the regioselectivity of the Diels-Alder reaction between unsymmetrically substituted dienes and dienophiles. Although ANH's treatment is mathematically simpler than other methods, ANH's method which laid emphasis on dissymmetrical transition state gave good results on decision of regioselectivity.

• Journal of the Korean Chemical Society
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• v.36 no.5
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• pp.770-779
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• 1992

Five (alkynylethoxymethylene)$Fe(CO)_4 complexes (1) are prepared through the reaction of Fe(CO)_5$ with alkynyllithium (R = n-Pr, cyclohexyl, t-Bu, trimethylsilyl, Ph) and subsequent O-ethylation of the resulting acyl anion complexes with ethyl fluorosulfonate. In the reactions of trimethylsilyl-substituted alkynylcarbene complex (1d) with 8 open-chain 1,3-dienes, ({\eta}^3-vinylcarbene)Fe(CO)3 complexes (2) are obtained as major products.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.159-160
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• 2006

We developed novel catalyst, PHENICS composed of the combination of a cyclopentadienyl group to perform a high catalytic activity and a bulky phenoxy group, which performs the production of high molecular weight polyolefin. The polymerization activity of PHENICS at high temperature is higher than well-known CGC catalyst. PHENICS showed the excellent ability of comonomer incorporation into polymer chain. The obtained copolymer had a high molecular weight. The PHENICS catalyst is also active to the copolymerization of ethylene and several vinyl comonomers such as styrene, norbornen, and conjugated dienes. We will discuss new cocatalysts for PHENICS to improve activity and the ability of molecular weight control.