• Communications of Mathematical Education
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• v.25 no.1
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• pp.21-45
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• 2011

It is the aim of this paper to find the requisites for the target problem solving process in reference to the base problem and to search the roles of those. Focusing on the structural similarity, analytic activity and comparative activity in stage of similar mathematical problem solving process, we tried to find the roles of them. We observed closely how four students solve the target problem in reference to the base problem. And so we got the following conclusions. The insight of structural similarity prepare the ground appling the solving method of base problem in the process solving the target problem. And we knew that the analytic activity can become the instrument which find out the truth about the guess. Finally the comparative activity can set up the direction of solution of the target problem. Thus we knew that the insight of structural similarity, the analytic activity and the comparative activity are necessary for similar mathematical problem to solve. We think that it requires the efforts to develop the various programs about teaching-learning method focusing on the structural similarity, analytic activity and comparative activity in stage of similar mathematical problem solving process. And we also think that it needs the study to research the roles of other elements for similar mathematical problem solving but to find the roles of the structural similarity, analytic activity and comparative activity.

• Korean Journal of Biological Psychiatry
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• v.7 no.2
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• pp.140-146
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• 2000

P450 CYP2D6 enzyme(=debrisoquine hydroxylase) is known to metabolize many neuroleptics and some genetic polymorphisms in the CYP2D6 gene were reported to be associated with tardive dyskinesia(TD). We investigeted the association of two genetic polymorphisms in the CYP2D6 gene, $CYP2D6^*4$ and $CYP2D6^*10$, with TD in Korean schizophrenic subjects. Subjects consisted of 71 Korean schizophrenics and TD was evaluated using the Abnormal Involuntary Movement Scale (AIMS). There were no statistically significant differences in the demographic variables of age, male to female percentage and the current antipsychotic(CPZ equivalent) dose between the group with TD and the group without TD. But the duration of antipsychotic drug exposure was significantly higher in the group without TD(p=0.000, by independent t-test). The mean AIMS score in the group with TD was $11.2{\pm}6.6$(S.D.). Genotypings for the presence of $CYP2D6^*4$ and $CYP2D6^*10$ were done using PCR amplifications and endonuclease digestions. There were no statistically significant genotypic and alleleic associations between TD and $CYP2D6^*4$(by chisquare tests), and between TD and $CYP2D6^*10$(by chi-square tests). These results indicate that the $CYP2D6^*4$ and $CYP2D6^*10$ polymorphisms have no significant roles in the causation of TD.

• 대한공업교육학회지
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• v.38 no.1
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• pp.275-297
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• 2013

Invention Teacher Education(ITE) is composed of Invention Contents Standards(ICS) and Invention Education Standards(IES). The purpose of this study is to developing ICS of ITE. To achieve the goal, we used the methods of research; analyzing advanced research, content analysis, development, survey, verify the validity. The research results of this study is summarized as follows. ICS is composed of 10 large areas; the concept and characteristic of invention, invention and society, invetion in living, creativity development, invention and design, invention and solving problem, convergence of knowledge and invention, invention project, intellectual properties and patent application, invention and management of technology. 10 large areas has 20 core contents and 90 subordinate elements. ICS will be based on the academic of developing programming besides it will be reference of standards in the case of progressing invention education.

• Journal of the Korean School Mathematics Society
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• v.12 no.4
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• pp.545-562
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• 2009

Calculus is used in various parts of human life and the basis of social science such as economics and public administration. Yet that is still considered important in the field of science and technology only, and there have been a lot of disputes on that phenomenon. Fortunately, calculus is going to be taught as part of the academic high school second-year mathematics curriculum in and after 2010. Students who face calculus for the first time should be helped not to lose interest in differentiation learning, not to be apprehensive of it nor to avoid it. The purpose of this study was to examine the types of errors made by students in the course of solving differentiation problems in an effort to lay the foundation for differentiation education. A pilot test was conducted after generalized differentiation problems to which students were usually exposed were selected, and experts were asked to review the pilot test. And then a finalized test was implemented to make an error analysis according to an error type analysis framework to serve the purpose.

• Korean Journal of Environmental Agriculture
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• v.17 no.4
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• pp.329-334
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• 1998

This study was conducted in order to investigate removal rate of organic matter, nitrogen and phosphorus to reduce environmental polluation with treatment to attach combined septic tank to 3 stage soil filter after mixing anaerobic treated water of livestock wastewater and low concentrated wastewater generated in farm house. Because anaerobic filter bed was packed in combined septic tank and a microorganism was accumulated in combined septic tank with increasing hydraulic retention time(HRT), if HRT $4{\sim}12day$, CODcr was removed $63.4{\sim}84.0%$. Also, $NH_4\;^+-N$ and $PO_4\;^{3-}-P$ were removed $3.9{\sim}5.4%$ and $18.3{\sim}29.0%$, respectively. In being re-treated by 3 stage soil filter, although hydraulic loading rate was gradually increased, CODcr, $NH_4\;^+-N$ and $PO_4\;^{3-}-P$ were removed above 90% due to filtration, adsorption, ion exchange, and action of soil microorganism. Generally, the attached treatment of combined septic tank and 3 stage soil filter did suitably treat livestock wastewater to water standard of discharge applied from '96 year, in view of decreasing pollution loading amount and recycling of agricultural water.

• Korean Journal of Food Science and Technology
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• v.32 no.4
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• pp.936-941
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• 2000

To assess functional properties of chungkugjang (CK), a traditional Korean soyfood, fermented with black beans at $42^{\circ}C$ for 72 hrs, some biological activities of methanol extract of CK and the changes in phytoesterogen (daidzein, genistein) contents during fermentation were investigated. The methanol extract of CK (MEC) prepared with soybean had no or a little antibacterial activity. MEC prepared with black bean inhibited the growth of all bacteria tested, and MEC of small black bean was higher in antibacterial activity than that of large black bean. Hydrogen-donating activities of MEC of large and small black bean were 76.4 and 75.5%, respectively, which were higher than that of soybean being 67.3%. Nitrite-scavenging activity was found to be above 90% in all MECs tested as compared with control group. MEC showed strong antioxidant activities against both peroxidation of linoleic acid and $H_{2}O_{2}-FeSO_{4}-induced$ peroxidation of rat liver homogenate. The antioxidant activities were high in the order of small black bean, large black bean and soybean. Contents of genistein and daidzein were gradually increased during fermentation of CK. The isoflavones were higher in black bean CK than in soybean CK and higher in large black bean CK than in small black bean CK. In black beans genistein content was about twice as much of daidzein.

• Journal of Korean Society of Rural Planning
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• v.5 no.1 s.9
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• pp.95-103
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• 1999

The purpose of this study is to find out the distribution of underground biomass and its soil stabilizing effects. Bamboo and grass were examined and compared. 1. Thirty 'soil & root' samples were collected to the depth of 30cm with Impact-corer, and then divided into three sections(0-10cm, 10-20cm, 20-30cm). Each piece had a volume of $950cm^3$ and the underground biomass was separated from the soil particles by washing with flowing water. The average underground biomass rates of bamboo and grass were 10.8% and 4% of each sample, respectively. The rate of grass root biomass declined with depth, but the bamboo root biomass was at peak at around 20cm depth. 2. The shear strength was measured with con-penetration tester at each sample collecting site. Three measurements were made at each depth(0-10cm, 10-20cm, 20-30cm) and were compared with the impact counts needed to insert the corer to the depth of 30cm. The shear strength has clear correlations with underground biomass. The more underground biomass, the higher shear strength. The shear strength of bamboo was about three times larger than the grass.

• Journal of the Korean Wood Science and Technology
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• v.29 no.2
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• pp.84-90
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• 2001

To investigate morphological characteristics of zephyr produced from two bamboo species, Phyllostachys nigra var. henonis and Gigantochloa apus, basic anatomic properties were examined by scanning electron microscopy and image analysis. According to SEM observation, zephyr from Phyllostachys nigra var. henonis was not of uniform in shape and showed macro crack between vascular bundle sheaths. This may be attributes to the sclerenchymatous fibers connected closely, thus resulting in difficult separation of intercellular layer. Zephyr from Gigantochloa apus was of uniform in shape, which may be caused by easy separation of intercellular layer of sclerenchymatous fibers having thin cell wall and large cell lumen. By image analysis in cross section of two species, the ratio of vascular bundle sheaths and cell wall ratio of sclerenchymatous fibers were examined. The ratio of vascular bundle sheaths in Phyllostachys nigra var. henonis was lower than that in Gigantochloa apus. However, cell wall ratio of sclerenchymatous fibers in Phyllostachys nigra var. henonis was higher than that in Gigantochloa apus.

• Korean journal of applied entomology
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• v.29 no.4
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• pp.230-237
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• 1990

Studies were carried out to examine seasonal occurrence and emergence pattern of the onion fly, Delia antiqua (Meigen), in the field of Chinju city in Gyeongnam province from 1984 to 1987. Trap catch revealed that the onion fly had three generations in a year, the second flight being partial; the peaks of adult occurrence were at mid April for the overwintered generation (1st flight), at early June for the first generation (2nd flight), and at the period from late September to early October for the autumn generation (3rd flight). It was shown that parts of the pupae in the first and almost all of the pupae in the second (or autumn) generation underwent summer diapause. The pupal periods were less than 22.4 days for the non-diapaused pupae, while those of the diapause. The pupal periods were less than 22.4 days for the non-diapaused pupae, while those of the diapaused pupae were form 8.5 to 145 days in the first generation in he filed, being shorter for the pupae pupated later. This resutled in synchronization on the emergence of these diapaused pupae at late September, with the adults from the second generation pupae. The ratio of diapausing pupae increased among the later pupated ones in the first generation ; the pupae which had been pupated in early May included 43.8% of diapausing pupae, while more than 86.7% of the pupae were under diapausing state for the pupae pupated in late May and thereafter. More than 93.3% of the pupae went into diapause, regardless of pupation time for the second generation.

• Journal of Environmental Science International
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• v.16 no.4
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• pp.449-458
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• 2007

Research results for the pressure drop variance depending on operation conditions such as change of inlet concentration, pulse interval, and face velocity, etc., in a pulse air jet-type bag filter show that while at $3kg/cm^2$ whose pulse pressure is low, it is good to make an pulse interval longer in order to form the first layer, it may not be applicable to industry because of a rapid increase in pressure. In addition, the change of inlet concentration contributes more to the increase of pressure drop than the pulse interval does. In order to reduce operation costs by minimizing filter drag of a filter bag at pulse pressure $5kg/cm^2$, the dust concentration should be minimized, and when the inlet dust loading is a lower concentration, the pulse interval in the operation should be less than 70 sec, but when inlet dust loading is a higher concentration, the pulse interval should be below 30 sec. In particular, in the case that inlet dust loading is a higher concentration, a high-pressure distribution is observed regardless of pulse pressure. This is because dust is accumulated continuously in the filter bag and makes it thicker as filtration time increases, and thus the pulse interval should be set to below 30 sec. If the equipment is operated at 1m/min of face velocity, while pressure drop is low, the bag filter becomes larger and thus, its economics are very low due to a large initial investment. Therefore, a face velocity of around 1.5 m/min is considered to be the optimal operation condition. At 1.5 m/min considered to be the most economical face velocity, if the pulse interval increases, since the amount of variation in filter drag is large, depending on the amount of inlet dust loading, the operation may be possible at a lower concentration when the pulse interval is 70 sec. However, for a higher concentration, either face velocity or pulse interval should be reduced.