• Journal of Radiation Protection and Research
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• v.26 no.3
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• pp.133-137
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• 2001

Spatial and time distributions of x-rays and neutrons from Hokkaido University 45 MeV electron linac facility were measured and compared with the calculation. In the calculation, x-rays in a Pb-target were evaluated using the EGS-code. The x-rays and the neutrons from the target to the facility building boundary and skyshine process outside the facility building were simulated with the EGS and the MCNP respectively.

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2005.11a
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• pp.162-162
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• 2005

• BMB Reports
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• v.41 no.5
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• pp.358-362
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• 2008

RNA interference (RNAi) is the process of sequence-specific gene silencing. However, RNAi efficiency still needs to be improved for effective inhibition of target genes. We have developed an effective strategy to express multiple shRNAs (small hairpin RNA) simultaneously using multiple RNA Polymerase III (Pol III) promoters in a single vector. Our data demonstrate that multiple shRNAs expressed from Pol III promoters have a synergistic effect in repressing the target gene. Silencing of endogenous cyclophilin A (CypA) or key HIV viral genes by multiple shRNAs results in significant inhibition of the target gene.

• Proceedings of the Korean Society of Life Science Conference
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• 2005.04a
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• pp.202-202
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• 2005

• Journal of Chest Surgery
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• v.45 no.5
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• pp.323-325
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• 2012

Pulmonary tumor embolism can be a cause of respiratory failure in patients with cancer even though it occurs rarely. We describe a 56-year-old man who underwent a pulmonary tumor embolectomy using cardiopulmonary bypass on beating heart combined with inferior vena cava embolectomy and right radical nephrectomy. Aggressive surgical treatment in this severe case is necessary not only to reduce the fatal outcome of pulmonary embolism in the short run, but also to improve the oncological prognosis in the long term.

• Proceedings of the Ginseng society Conference
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• 2004.12a
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• pp.61-61
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• 2004

• Communications of Mathematical Education
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• v.19 no.4 s.24
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• pp.715-731
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• 2005

There are five contexts of division algorithm of fractions such as measurement division, determination of a unit rate, reduction of the quantities in the same measure, division as the inverse of multiplication and analogy with multiplication algorithm of fractions. The division algorithm, however, should be taught by 'dividing by using reciprocals' via 'measurement division' because dividing a fraction by a fraction results in 'multiplying the dividend by the reciprocal of the divisor'. If a fraction is divided by a large fraction, then we can teach the division algorithm of fractions by analogy with 'dividing by using reciprocals'. To achieve the teaching-learning methods above in elementary school, it is essential for children to use the maniplatives. As Piaget has suggested, Cuisenaire color rods is the most efficient maniplative for teaching fractions. The instruction, therefore, of division algorithm of fractions should be focused on 'dividing by using reciprocals' via 'measurement division' using Cuisenaire color rods through analogy if necessary.

• Education of Primary School Mathematics
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• v.22 no.2
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• pp.113-127
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• 2019

The purpose of this study is to justify the fraction division algorithm in elementary mathematics by applying the definition of natural number division to fraction division. First, we studied the contents which need to be taken into consideration in teaching fraction division in elementary mathematics and suggested the criteria. Based on this research, we examined whether the previous methods which are used to derive the standard algorithm are appropriate for the course of introducing the fraction division. Next, we defined division in fraction and suggested the unit-circle partition model and the square partition model which can visualize the definition. Finally, we confirmed that the standard algorithm of fraction division in both partition and measurement is naturally derived through these models.

• 대한예방의학회:학술대회논문집
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• 1999.10a
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• pp.200-201
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• 1999

• 대한생식의학회:학술대회논문집
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• 2004.11a
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• pp.35-36
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• 2004