• Bulletin of the Korean Chemical Society
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• v.17 no.5
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• pp.419-424
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• 1996

A dendrimeric silane containing 162 allylic end groups is prepared via a divergent growing approach. The reaction process of the repetitive alkenylation and hydrosilylation cycles was monitored by NMR spectroscopic attachments. Both steps provided almost quantitative yields of pure silane dendrimers.

• Journal of the Korean Society of Propulsion Engineers
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• v.19 no.6
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• pp.64-71
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• 2015

Spinning process is generally used for manufacturing axisymmetrical, thin-walled thickness and hollow circular cross-section parts. Traditional spinning technology is classified to conventional spinning and power spinning(shear spinning and flow forming). Literature surveys of spinning application for regenerative cooling chamber and divergent nozzle of liquid propellent rocket thrust chamber have been conducted. Most spinning technology has been used mandel for manufacturing chamber and nozzle. Recently, hot spinning has been used much compared to traditional cold spinning.

• Journal of the Korean Home Economics Association
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• v.43 no.4 s.206
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• pp.161-172
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• 2005

The present study investigation the effect of a project approach program on children's cognitive styles. It examined closely the characteristics and processes of the project approach program to determine its impact on children's individual cognitive styles such as divergent thinking, field independence, and reflection. The subjects were 384-year-old children. Eighteen children were assigned to the experimental group and twenty to the control group. Pretest-treatment-posttest design was adopted for this study. Collected data were analyzed with SPSS Win 10.0 and processed statistically using average, standard deviation, and ANCOVA. For the children's divergent thinking, the children with the project approach program showed significant difference in fluency and flexibility, but no difference in originality and elaboration, compared to the children in the control group. Children with the project approach program showed more field independence than those in the control group. Children with the project approach program showed no difference in reflection. These results showed that the project approach pro!3ram partly influenced the children's cognitive styles.

• Journal of Korean Academy of Nursing Administration
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• v.18 no.4
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• pp.442-451
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• 2012

Purpose: The purpose of this study was to identify effects of action learning approaches on learning outcomes of students taking nursing management courses. Methods: The questionnaire surveys were completed between March 2011 and June 2012 by 109 undergraduate seniors in the nursing department of C University. Survey data were obtained 3 times: before, in and after the study of nursing management. The course consisted of lectures and clinical practices. Learning outcomes were measured through problem solving skills, team efficacy, and class satisfaction. Collected data were analyzed using repeated measures ANOVA with the SPSS 20.0 program Results: Scores for problem solving skills (F=13.67, p<.001) and team efficacy (F=4.49, p=.012) showed statistically significant increases after the course. The scores also increased significantly after the lectures for 5 of 9 problem solving skill subscales: analysis skill, divergent thinking, decision making, assessment, feedback, and after the clinical practices for 2 subscales: divergent thinking, and execution and risk taking. Class satisfaction score also increased after both the lectures and the clinical practices. Conclusion: The findings from this study suggest that an action learning approaches for nursing management courses would be a useful teaching and learning method to achieve learning outcomes.

• Korean Institute of Interior Design Journal
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• v.16 no.2 s.61
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• pp.63-70
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• 2007

Analogy in problem solving is similarity-based reasoning facilitated by verbal and visual operation. This similarity-based reasoning generally supports initial phase of idea search. Therefore, this study intends to infer the types of problem solving by tracing the analogy use of verbal and visual representation through a experimental research. According to the result of this research, the types of problem solving by analogy are classified into 'evolving', 'divergent', and 'poor conversion' type. Firstly, 'evolving type' is distinguished between 'combination type' associated different contents to develope a new design and 'transformation type' associated similar words and sketches to be continuously revised and developed. In these types usually structural analogy rather than surface analogy is used. Secondly, in 'divergent type' associated words or sketches are individually represented, and among them one design solution is selected. In this type usually surface analogy is used. Thirdly, in 'poor conversion type' interaction between verbal representation and visual representation does not go on smoothly, and the generation of idea is poor. In here surface analogy is mostly used. These findings could form the basis of skill development of idea generation and conversion in design education.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.4
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• pp.954-964
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• 2015

In this research, an overlapped illumination model was newly proposed for designing a freeform LED lens with a uniform illuminance distribution on its illuminating plane. Based on the proposed model and conventional illumination models, freeform lenses were designed and their performances and tolerances were compared. As a result of the tolerance analysis about thickness change in lens, position, size change, central direction change of light emission and characteristic change in LED source. This proposed model and divergent illumination model are similar to the performance about central direction change of light emission in LED source. but the uniformity illumination value in this proposed model is more remarkably value than it in divergent illumination model about characteristic change in LED source.

• Korean Institute of Interior Design Journal
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• v.22 no.4
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• pp.33-40
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• 2013

This study aims to recognize that creative thinking methodologies can be adopted in the spatial design. The concept of 'Convergent' and 'Divergent' used in structure of intellect model by Guilford is chosen to understand the character of creative thinking methodologies. Technical and physical contradictions is analyzed for '40 inventive principles' of TRIZ and spatial design works. Through this study, we recognize that the creative thinking methodologies consist of analysis, idea generation and evaluation phase. The psychological inertia that limits the creative thinking should be move away from solving problem, and convergent and divergent thinking have peculiarities to be adopted in condition and to be harmonized, and to set the direction of solving technical problems through to reach the target point integrated way of thinking is needed. '40 inventive principles' by Altshuller are based on engineering and useful in many areas of fields. However some principles are not accepted in design process because these are not considered in design field and paradigm is changed from machine to nature. Nowadays, nature is a prime issue for sustainable human life, because it has sustainable recycle structure and saving energy ways. Thus, creative thinking, including TRIZ is useful in design education and progress, and should be an essential element to get a new design paradigm.

• Journal of Microbiology and Biotechnology
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• v.16 no.11
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• pp.1773-1777
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• 2006

We evaluated the usefulness of DNA microarray as a comparative genomics tool, and tested the validity of the cutoff values for defining absent genes in test genomes. Three genome-sequenced E. coli strains (K-12, EDL933, and CFT073) were subjected to comparative genomic hybridization with DNA microarrays covering almost all ORFs of the reference strain K-12, and the microarray results were compared with the results obtained from in silico analyses of genome sequences. For defining the K-12 ORFs absent in test genomes (reference strain-specific ORFs), we applied and evaluated the cutoff level of -1. The average sequence similarity between ORFs, to which corresponding spots showed a log-ratio of>-1, was $96.9{\pm}4.8$. The numbers of spots showing a log-ratio of <-1 (P<0.05, t-test) were 90 (2.5%) and 417 (10.6%) for the EDL933 genome and the CFT073 genome, respectively. Frequency of false negatives (FN) was ca. 0.2, and the cutoff level of -1.3 was required to achieve the FN of 0.1. The average sequence similarity of the false negative ORFs was $77.8{\pm}14.8$, indicating that the majority of the false negatives were caused by highly divergent genes. We concluded that the microarray is useful for identifying missing or divergent ORFs in closely related prokaryotic genomes.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2006.05a
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• pp.337-340
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• 2006

The present paper describes an experimental work to investigate a transonic resonance in supersonic jet that is discharged from a convergent-divergent nozzle. When the nozzle m: at low nozzle pressure ratios, the shock occurs within the divergent section of the nozzle. The transonic resonance of a jet flow is generated by an emission of strong acoustic tones due to the unsteadiness of the shock. A Schlieren optical system is used to visualize the supersonic jet flow In order to specify the flow resonance of a jet, acoustic measurements are performed to obtain noise spectra. The acoustic characteristics of transonic resonace are compared with those of screech tones. The results obtained show that unlike screech frequency, the transonic reso- nace frequency somewhat increases with increasing the nozzle pressure ratio.

• Transactions of the Korean Society of Mechanical Engineers
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• v.14 no.6
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• pp.1639-1644
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• 1990

Effects of radiation on the wall-friction and heat transfer in the convergent and divergent nozzle of a rocket motor are investigated in the present paper. Radiative heat transfer cools down the core gas, and the decrease in the gas temperature reduces the convective heat transfer on the wall. Radiation heat transfer is estimated by using mean-beam-length approach and core flow is assumed to be one-dimensional isentropic. The compressible thermal boundary layer is solved by a finite difference method. The Cebeci-Smith eddy viscosity model is adopted for the present study. Convective heat transfer is reduced at the throat of the nozzle and is almost compensated with an increase in radiative transfer. In the sequel total heat transfer rate is slightly reduced. However, radiation heat transfer is dominant in the converging part of the nozzle.