• The Journal of the Korea institute of electronic communication sciences
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• v.13 no.3
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• pp.593-600
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• 2018

Cellular automata (CA) have been applied to effective cryptographic system design. CA is superior in randomness to LFSR due to the fact that its state is updated simultaneously by local interaction. To apply these CAs to the cryptosystem, a study has been performed how to synthesize CA corresponding to given polynomials. In this paper, we analyze the recurrence relations of the characteristic polynomial of the 90 UCA and the characteristic polynomial of the 90/150 CA whose transition rule is <$00{\cdots}001$>. And we synthesize the 90/150 CA corresponding to the trinomials $x^{2^n}+x+1(n{\geq}2)$ satisfying f(x)=f(x+1) using the 90 UCA transition rule blocks and the special transition rule block. We also analyze the properties of the irreducible factors of trinomials $x^{2^n}+x+1$ and propose a 90/150 CA synthesis algorithm corresponding to $x^{2^n}+x^{2^m}+1(n{\geq}2,n-m{\geq}2)$.

• Macromolecular Research
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• v.16 no.1
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• pp.51-56
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• 2008

Spherical micelles of poly(styrene-b-isoprene) (SI) diblock copolymers in selective solvents have been reported to pack onto either face-centered cubic (fcc) or body-centered cubic (bcc) lattices. The selection rule for fcc and bcc lattices has been understood in terms of the intermicellar potentials, and they have been quantified using the ratio of the corona layer thickness to the core radius, $L/R_c$, as suggested by McConnell and Gast. In order to test the validity of the McConnell-Gast criterion, this study compared the $L/R_c$ values from various solutions i.e. nine SI copolymers in several different selective solvents. The McConnell-Gast criterion was not found to be a determining factor, even though it could explain the fcc/bcc selection qualitatively. From the phase diagrams, the transition between fcc and bcc phases was also considered as a function of concentration and temperature, and their physical mechanisms are discussed based on the recent mean-field calculation reported by Grason.

• The Journal of the Korea institute of electronic communication sciences
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• v.13 no.4
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• pp.819-826
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• 2018

The generalized Hamming weight is one of the important parameters of the linear code. It determines the performance of the code when the linear codes are applied to a cryptographic system. In addition, when the block code is decoded by soft decision using the lattice diagram, it becomes a measure for evaluating the state complexity required for the implementation. In particular, a bit-parallel multiplier on finite fields based on trinomials have been studied. Cellular automata(CA) has superior randomness over LFSR due to its ability to update its state simultaneously by local interaction. In this paper, we deal with the efficient synthesis of the pseudo random number generator, which is one of the important factors in the design of effective cryptosystem. We analyze the property of the characteristic polynomial of the simple 90/150 transition rule block, and propose a synthesis algorithm of the reversible 90/150 CA corresponding to the trinomials $x^2^n+x^{2^n-1}+1$($n{\geq}2$) and the 90/150 reversible CA(RCA) corresponding to the maximum weight polynomial with $2^n$ degree by using this rule block.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.5
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• pp.2497-2504
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• 2013

This study aims to analyze the 'Standard Drawings for School Facilities' issued by Seoul Education Committee in 1975 because it is the early example for middle school architecture. The results of this study are summarized as follows 1) In general trend of single-corridor type block plan, there are also changes in floor plan like no-corridor type block plan, $9.9{\times}6.6m$ classroom unit for the better daylight condition, built-in storage for students. 2) As for elevation design, it is characterized as daylight-oriented, functional exterior for without making full use of design elements. 3) Standardized dimensions are used as a rule in the height of story, ceiling, window sill and etc. Transitional characteristics of the early RC school architecture are found in exposed ceiling, incomplete insulation structure and mixed use of wood framed floor of earlier type. 4) Contrast to main school building, gymnasium shows the intend to express the symbolism of school architecture with diverse elevation design elements and the plasticity of building mass. 5) Separated plan of toilet and night-duty building also show the transitional characteristics. As conclusion, though showing the stereotyped school architecture, on the other hand, 'Standard Drawings for School Facilities' (1975) makes it possible to see the way of coping with the demands for school architecture in that time and the transition of school architecture. This is the main value of it as the material for the studies related to the history of educational facilities.