• Advances in materials Research
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• v.1 no.1
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• pp.1-12
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• 2012

There have been many efforts on the generating metal nanocrystals enclosed by high-index facets for the use as highly active catalysts. This paper describes a facile synthesis of Au trisoctahedra with high-index facets. In brief, the Au trisoctahdra were prepared by reduction of $HAuCl_4$ in N,N-dimethylformamide (DMF) containing poly (vinyl pyrrolidone) (PVP) and trace amount of $AgNO_3$. The Ag ions in the reaction solution played a critical role in controlling the trisoctahedral shape of the final product by underpotential deposition (UPD) on the Au surfaces. The as-prepared Au trisoctahedra were single crystal and enclosed by high-index {441}, {773} and {331} facets.

• Proceedings of the Korean Society of Life Science Conference
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• 2005.04a
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• pp.110-110
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• 2005

• Korean Journal of Health Education and Promotion
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• v.3 no.1
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• pp.99-111
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• 2001

Adolescent psychosocial smoking prevention programs have been successful, but limited in the magnitude of program effects on the reduction of smoking behaviors. This is primarily due to the mixed results of independent studies with program variations. This systematic, quantitative research synthesis is designed to identify program key factors that are likely to increase program effects. The present study examined school-based psychosocial smoking prevention programs (1978-1997)among students in grades 6 to 12 in the United States. Theoretical formulations in this analysis of mediating effects posit that program impact on knowledge and/ or skills is associated with less smoking behaviors among program participants. Knowledge factors investigated in this study included health effects, social consequences, social influences, and social norms. Skill factors included affective skill, self-efficacy, assertiveness, self-control, problem solving, and refusal skill. The findings from this study highlight the importance of social consequences knowledge factor and assertive communication skill factor in decreasing adolescent smoking behaviors.

• Journal of Microbiology and Biotechnology
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• v.16 no.3
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• pp.355-359
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• 2006

The functional stability of mRNA is one of the crucial factors affecting the efficiency of in vitro translation. As the rapid degradation of mRNA in the cell extract (S30 extract) causes early termination of the translational reactions, extending the mRNA half-life will improve the productivity of the in vitro protein synthesis. Thus, a simple PCR-based method is introduced to increase the stability of mRNA in an S30 extract. The target genes are PCR-amplified with primers designed to make the ends of the transcribed mRNA molecule anneal to each other. When compared with normal mRNA, the mRNA with the annealing sequences resulted in an approximately 2-fold increase of protein synthesis in an in vitro translation reaction. In addition, sequential transcription and translation reactions in a single tube enabled direct protein expression from the PCR-amplified genes without any separate purification of the mRNA.

• Journal of Korean Philosophical Society
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• v.148
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• pp.157-181
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• 2018

The aim of this essay is to identify elements of methodologies to investigate the development of Newtonian dynamics. This methodology involves the transformation and synthesis of preceding theories. My essay attempts to confirm my assertion by analyzing historical case of Newton's discovery of his dynamics. While discovering his mechanistic theory, Newton reconstructed theoretical concepts and structures of intellectual predecessors, such as Aristotle, Descartes, Galileo, and Kepler. Newton's synthesis was possible only after carefully reconstructing the appropriate and useful ideas of previous natural philosophers' ideas. As a result, Newtonian dynamics are completed with these modified and integrated concepts incorporated into Newton's law of motion and space-time concepts. This study consists of two parts. First, Lakatos' research program has been applied in order to analyze the structure of Newtonian dynamics. Second, the aforementioned methodologies of discovery are distilled from the case study.

• Journal of the Korean earth science society
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• v.26 no.5
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• pp.387-394
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• 2005

We have analyzed the science-gifted educational program (year 2002) at the Seoul National University in terms of its educational objectives, scientific models, and cognitive processes in scientific inquiry in order to provide insights into developing and improving science-gifted educational program. We assumed the following items as important factors for teaching scientifically gifted students: higher-order thinking skills involving synthesis domain in the educational objectives, highly abstract nature and complexity in the scientific models, cognitive processes of planning experiments in the cognitive processes in scientific inquiry. According to the analyzed results, the program has the following characteristics: (1) the rates of both higher and lower-order thinking skill domain in the educational objectives are similarly high, but the rate of synthesis domain is relatively low; (2) in the case of the scientific models, the rate of the multiple concepts and/or processes model is relatively low, while the level of the abstractness is relatively on average (3) cognitive processes of authentic scientific inquiry is not thoroughly reflected in the scientific inquiry activities, and very few cognitive processes of planning experiments factor is reflected. Therefore, we conclude in the synthesis domain in the educational objectives, multiple concepts and/or processes model, and cognitive processes of planning experiments should be especially reflected more on the science-gifted educational program in order to serve the needs of scientifically gifted students.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.7 no.6
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• pp.28-35
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• 1998

Computer simulation technique has been applied on the various engineering fields to reduce cost and development period. On this paper, we introduce a crane analysis program. Using this program, we can predict reaction force of each part or supporting force of truck crane on a personal computer system with out exclusive knowledge of multi-body dynamics. In order to consider the effect of boom flexibility according to each working condition, flexible dynamic theory is applied to the program. Actual crane model is analyzed on special work condition using this program and the results are compared with those of rigid boom model.

• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.240-240
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• 2007

• Bulletin of the Korean Chemical Society
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• v.24 no.5
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• pp.617-622
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• 2003

D-erythro-sphinganine 1 and L-threo-sphinganine 2 have been prepared in the enantiomerically pure form by the chirospecific manner. Key intermediates, 2-amino-3-hydroxy-4-pentenoates 8 and 12, were obtained from L-glucono-1,5-lactone and L-gulonic acid g-lactone via a simultaneous dealkoxyhalogenation.

• Journal of the Korean Society for Precision Engineering
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• v.6 no.4
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• pp.126-135
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• 1989

In this study, in order to perform dynamic design of machine tools reasonably and effectively, a method was formulated to be applicable to the structures connected by joints having elasticity and damping by using substructure synthesis method. And to analyze chatter-free performance, a 3 dimensional cutting dynamics theory was used. Computer program package for the dynamic design of machine tools was developed by combining those and spplied to improvement of performance of NC lathe. Also, the optimization in the structural modifications of machine tool substructure was studied by evaluating the effects of the substructural modifications on total system performance.