• Korean Journal of Child Studies
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• v.33 no.5
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• pp.19-35
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• 2012

The purposes of this study were to investigate how children's categorization differs in object categorical hierarchy and to examine whether these aspects were different according to the children's age of 18 months, 24 months, 30 months. The participants consisted of 120 young children aged 18 months, 24 months, and 30 months from 31 child-care centers located in middle-income regions of Seoul and Kyonggi Province. The major findings were as follows : First, all the children from all three age groups could consistently differentiate the superordinates; however, they could not consistently differentiate basic categories. Second, 24 month appears to be a critical change period in category development. Third, as the children become older, they are able to acquire more knowledge regarding categories. These results suggested that the advent of ordering, in terms of basic categories as well as superordinates which occurred around the age of 24 month, was confirmed in category development.

• Journal of the Korean Society of Industry Convergence
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• v.20 no.1
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• pp.1-7
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• 2017

Most conventional processors execute program instructions in a sequential manner. On the other hand, VLIW processor can execute multiple instructions at the same time. It exploits instruction level parallelism to improve system performance. To that end, program code should be rearranged to VLIW instruction format by a compiler. The compiler determine an optimal execution order of instructions of a program code. This instruction ordering is also called instruction scheduling. The scheduling is an algorithm that decides the execution order for instruction codes in loop parts of a program so that the instruction level parallelism can be maximized. In this research, we apply an existing scheduling algorithm to a VLIW FCC and describe analysis results to further improve its performance. And, we present a solution to solve some limitation of the existing scheduling technique. By using our solution, FCC's performance can be improved upto 32% compared to the existing scheduling only setting.

• Macromolecular Research
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• v.17 no.6
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• pp.365-377
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• 2009

In this feature article, we briefly review the new methods we have utilized recently in the investigation of morphology and phase behavior of block copolymers. We first describe the chromatographic fractionation method to purify block copolymers from their side products of mainly homopolymers or block copolymer precursors inadvertently terminated upon addition of the next monomer in the sequential anionic polymerization. The chromatographic method is extended to the fractionation of the individual block of diblock copolymers which can yield the diblock copolymer fractions of different composition and molecular weight, which also have narrower distributions in both molecular weight and composition. A more detailed phase diagram could be constructed from the set of block copolymer fractions without the need of acquiring many block copolymers each prepared by anionic polymerization. The fractions with narrow distribution in both molecular weight and composition exhibit better long-range ordering and sharper phase transition. Next, epitaxial relationships between two ordered structures in block copolymer thin film is discussed. We employed the direct visualization method, transmission electron microtomography(TEMT) to scrutinize the grain boundary structure.