• Journal of Educational Research in Mathematics
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• v.18 no.4
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• pp.455-467
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• 2008

We need to reflect the establishment of meaning and level of 'proof and argumentation in middle school mathematics'. It should be considered as human activity through communication in community. Thus, we should design instruction from this standpoint. From this point of view, we had been operated 'Geometry Inquiry Class' aimed at middle school students in eighth grade for two years to improve current geometry class in middle school. In this study, we will observe how individual students' original proof schemes are developed and accepted to the class through the process of mutual negotiation between the teacher and students. The episode with four phases begins with the initial proof schemes students have offered. Through the negotiation of class participants, it gives birth to the proof scheme unique to the current geometry classroom. Why do we pay attention to the process? It is because we think that the value of this type of instruction lies in the process of communication and mutual understanding and mutual reference, not in the completeness of the final product. This is the very appropriate proof in the middle school mathematics classroom.

• Journal of Educational Research in Mathematics
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• v.25 no.2
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• pp.225-240
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• 2015

In this study, we investigated the representativeness of proofs in school mathematics, based on the extension of the midpoint connector theorem for the quadrilateral. To this end, we considered a variety of quadrilateral and proved their extensions of the midpoint connector theorem, and identified the relationships between them, therefore seemed that the proof in school mathematics has a representativeness. On the other hand, in the survey based on this information, students were found only some types of quadrilateral and completed easily the proofs for each quadrilateral they found, but students tended to use other proof or mathematical concepts, if the target figures changes in despite of proving the same mathematical fact. Thus, students were more difficult to figure out the relationship between the proofs. From these facts, we know that students are poorly understood the representativeness of proofs to understand the relationship between concrete proofs and to generalize it, though they are able to proof to the specific figures. Therefore it can be seen that the proof activity needs to be done with organic and semantic.

• Journal of the Korea Society of Computer and Information
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• v.20 no.7
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• pp.115-120
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• 2015

The old people's feelings, emotions, and self-evaluative judgements fluctuate overtime. The purpose of this paper is to proof relations among well-being factors in social activity. Major results of this paper was as follows. First, the social activity participated elderly had higher health status, self-esteem, mental-health, and successful aging than the non-participated elderly. Second, self-esteem and mental health were exposed as important variable for all of the two groups to improve the successful aging. Thus, self-esteem and mental health can become significant indicator of self-empowering and psychological resilience. Third, the strongest total causal effect of successful aging was health status in social activity participated elderly, while self-esteem was the greatest total causal effect of it in the non-participated elderly. Health status had higher indirect effect of successful aging than direct effect of it in both of them.

• Journal of Microbiology and Biotechnology
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• v.8 no.6
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• pp.669-675
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• 1998

Taq DNA polymerase exhibits a sizable drawback compared to the other thermophilic DNA polymerases in that it demonstrates lower proof-reading activity due to the deficiency of 3'-5'exonuclease activity. A study was undertaken to improve the 3'-5' exonuclease activity in the PCR of Taq DNA polymerase. The three-dimensional structural alignment of the polymerase and 3'-5' exonuclease domains from the pol I family DNA polymerases explains why Taq DNA polymerase has just a background level of 3'-5'exonuclease activity. A comparison indicated that the two polymerase domains are very similar in primary and tertiary conformations, even though Taq DNA polymerase carries a much shorter 3'-5'exonuclease domain than that of E. coli DNA polymerase I. Those two polymerase domains were interchanged between Taq DNA polymerase and E. coli DNA polymerase I. The 3'-5' exonuclease domain from E. coli DNA polymerase I was separated and pasted into the polymerase domain of Taq DNA polymerase I, which resulted in a functional fusion-Stoffel fragment. The 3'-5'exonuclease activity of the fusion-Stoffel fragment increased up to 48% of the value of the Klenow fragment, while that of Taq DNA polymerase remained at 6.0% of the Klenow fragment.

• Fashion & Textile Research Journal
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• v.11 no.5
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• pp.827-832
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• 2009

The purpose of this study is to scientifically proof possibility of development of natural dye which has antimicrobial activity with Chelidonium majus var. asiaticum. For that silk fabrics dyed with Chelidonium majus var. asiaticum extracts were tested for anti-microbial activity. Bacterials used for test of anti-microbial activity were Staphylococcus aureus ATCC 6538, Klebsiella pneumoniae ATCC 4352 and Trichophyton mentagrophytes IFO 5466. The results of experiment were as follows ; 1. The more the number of times of dyeing increase the more value of K/S increased. 2. Reduction of bacterium against Staphylococcus aureus ATCC 6538 of silk fabrics dyed with Chelidonium majus var. asiaticum extracts was 99.9% without reference to the number of times of dyeing. 3. Reduction of bacterium against Staphylococcus aureus ATCC 6538 of silk fabrics dyed with Chelidonium majus var. asiaticum extracts was 99.9% after irradiation of 20 hour without reference to the number of times of dyeing. 4. Reduction of bacterium against Staphylococcus aureus ATCC 6538 of silk fabrics dyed with Chelidonium majus var. asiaticum extracts was over 94.8% after dry cleaning. As above silk fabrics dyed with Chelidonium majus var. asiaticum extracts were acquired a high anti-microbial activity against Staphylococcus aureus ATCC 6538.

• Natural Product Sciences
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• v.16 no.4
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• pp.239-244
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• 2010

Protein tyrosine phosphatase 1B (PTP1B), a negative regulator of insulin signaling, has served as a potential drug target for the treatment of type 2 diabetes. The MeOH extracts of twenty-nine medicinal plants, traditionally used in Vietnam as anti-diabetes agents, were investigated for PTP1B inhibitory activity in vitro. The results indicated that, most materials showed moderate to strong inhibitory activity with $IC_{50}$ values ranging from $3.4\;{\mu}g/mL$ to $35.1\;{\mu}g/mL$; meanwhile, eleven extracts (37.9%) could demonstrate PTP1B activity with $IC_{50}$ values less than $15.5\;{\mu}g/mL$; sixteen extracts (55.2%) could demonstrate PTP1B activity with $IC_{50}$ values ranging from $15.5\;{\mu}g/mL$ to $35.1\;{\mu}g/mL$. The study may provide a proof, at least in a part, for the ethno-medical use in diabetes disease of these plants.

• Journal of the Korean Society of Clothing and Textiles
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• v.30 no.8
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• pp.1178-1187
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• 2006

The purpose of this study is to conduct a questionnaire survey on the actual conditions of the working uniform and protective equipment put on by street cleaners, then to identify their inconvenience and problems and to draw solutions to improve them, and finally to design a spring-and-autumn street cleaner uniform which has enhanced functionalities such as motional flexibility, safety and soil proof. The questionnaire survey of this study was done by street cleaners who were in charge of street cleaning and collecting the recyclable waste. The result of this study, easily worn-out parts of the working clothing were the sleeve hems and the front part on the upper uniform, and the trouser hems and zipper on the lower uniform. Easily soiled parts were the sleeve hems, parts of arm on the upper uniform, and the trouser hems and knee parts on the lower uniform. Based on the results of the questionnaire survey, the sample uniforms were designed in consideration of material, design and pattern. A soil-proof material was used for easily soiled parts such as sleeve hems, knee parts and trouser hems. Reflective material was applied to the parts such as chest, back and the side lines of sleeves and trousers to raise visibility in working and to ensure safety. A crease was given to each side of the back. The height of sleeve cap was lowered to lift the motional flexibility of back and arm parts. Darts were applied to elbow and knee parts for a three-dimensional design. Gussets were inserted in the thigh part to give it activity. Then quantitative evaluation and a sensory evaluation, which was composed of outward appearance, motional flexibility and fitness for field operation, were conducted. According to these evaluations, the sample uniform was found to be more satisfactory than current uniform.

• Journal of Applied Reliability
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• v.1 no.2
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• pp.79-93
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• 2001

Recently, new aspects of paints such as a beautiful appearance, use of environmentally friendly paints, etc., in addition to the superior performance of paints have been requested for industrial paints including the paints for heavy construction equipment and others. Particularly, the quality of appearance of coating affects the sales of heavy construction equipment. And the necessity for the paints to have a superior weather-proof property without changing the luster or color even after long-time exposure to the open air is emphasized. The change in the surface color and luster of the paint due to the natural environment progresses very slowly, and it takes a long time to verify material properties when developing new paints. In order to improve such methods, weathering tests are performed in many laboratories as a test for accelerating aging of coating, and the lifetime of the products is estimated through evaluation of the weathering (environment-proof) quality of paints. However, not a great deal of research activity has been conducted up to the present time since the interrelationship between the actual results of testing and field data is different for each paint and it takes a long time to study relevant materials. Therefore, introduced in the present study is the estimation of the change in the quality of appearance of coating in the field through the accelerated aging test among the cases of improvement of the quality of appearance of the urethane paint for heavy construction equipment.

• Fashion & Textile Research Journal
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• v.7 no.4
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• pp.371-377
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• 2005

The purpose of this study is to consider 1990s fashion design involving the utility of function which is the essence of modernism. First, documentary studies about the aesthetic value of the utility of function throughout the 20th century sociocultural contexts has been done. Second, content analysis of articles in American "Vogue" from 1990 to 2002 has been accomplished to hold the actual proof for the utility of function in postmodernism fashion. As a result, the utility of function has been defined the utility of body activity, the utility of practical use, and the utility of mechanical product. According to contents analysis, new aspects has been introduced in use of high-tech fabrics, ornaments, and mass customization in 1990s. In conclusion, the utility of function in fashion has been improved in accordance with the change of sociocultural contexts and women's wants.

• 전기의세계
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• v.30 no.10
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• pp.639-644
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• 1981

PVC is a kind of electric insulation polymer. But we get some deteriorations in electrical characteristics of the PVC, when it is used on the radioactive field. In order to find out the cause of the deterioration, we investigate the surface-resistance, volume-resistance, dielectric constant and dielectric loss angle of the soft and hard PVC which is irradiated by the Co$^{60}$ .gamma. radioactivity. From the experiment, we can conclude the followings 1. Radio-activity proof characteristic in the soft PVC is stronger than in the hard PVC. 2. The resistance of PVC which is irradiated by the radio-activity decrease exponentially. 3. The dielectric constant and the dielectric loss angle of PVC irradiated by Co$^{60}$ .gamma.ray reach maximum value in first few time.