• Applied Chemistry for Engineering
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• v.7 no.3
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• pp.496-503
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• 1996

Aromatic and aliphatic copolyesters for the dispersing agent were synthesized by two stage reaction, esterification and polycondensation. Copolyesters were blended with PET in the melt state and their thermal and rheological properties were investigated. From GPC analysis Mn's and Mw's of copolyesters were about 30000 and 65000g/mol, respectively. From DSC experiment copolyesters had melting range of $90{\sim}150^{\circ}C$. Copolymer composition was in good agreement with comonomer feed ratio from $^1H$-NMR analysis. Copolyesters and SPA (standard sample) were blended with PET in the melt state. From DSC experiment, copolyesters and SPA were miscible with PET. From the dynamic melt viscosity experiment, melt viscosity of blended sample was increased as the content of aromatic copolyester was increased, while it was decreased as the content of aliphatic and SPA were increased. As for volume resistivity of dry color containing carbon black and copolyesters with dispersing time, aromatic copolyester showed highest value. It was conferred from this result that aromatic copolyester was the best dispersing agent for carbon black in PET resin.

• Journal of Distribution Science
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• v.4 no.2
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• pp.81-106
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• 2006

The value of Its visitors is very important factors on selection of a Spa & Resort. The first detailed purpose of this paper is to analyse the differences of select behaviors of a Spa & Resort according to the types of values of the visitors. The second aim is to conduct a research on the characters of select behaviors of the visitors. The third aim is to analyse the degree of satisfaction of the visitors, re-visitation and the intention of recommendation. The fourth purpose is to provide useful materials on analysis about the values of the visitors at various Spa & Resorts and to trigger dramatic effect of recuperation, relaxation with its visitor's needs met, the maximum of hotel's management profit at Spa & Resort's area and programs to activate the region's economy. Factor Analsis Routine of SPSS Windows Version 10.0 was applied to accomplish the issues of the study. The Applied analysis by research process are as follows; This paper applied Frequency analysis to figure out interviewee's demographic characters and various using types of the visitors, using their experience of visiting, Select influence, Visiting period, Accommodation they use, Accompanyist, Costs, Season, Transportation, The necessary time. This paper showed important correlation between the visitors' select attributes and behaviors after using it, between their personal value and behaviors after using it, between their individual value, motive of use and their select behavior of destinations. In accordance with it, Managers or developer of a Spa & Resort should make a plan after a sufficient review of the visitors' individual value. The visitor's value is changing continuously according to the change of spatial, occasional environment and should be assessed by those changes.

• Proceedings of the Costume Culture Conference
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• 2000.09a
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• pp.59-60
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• 2000

• Proceedings of the Costume Culture Conference
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• 2001.04a
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• pp.53-54
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• 2001

• Proceedings of the KHMA Conference
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• 2012.05a
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• pp.371-371
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• 2012

• Proceedings of the Korean Nuclear Society Conference
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• 2002.10a
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• pp.197.2-197
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• 2002

• ETRI Journal
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• v.37 no.1
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• pp.54-60
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• 2015

The use of serial concatenated codes is an effective technique for alleviating the error floor phenomenon of low-density parity-check (LDPC) codes. An enhanced sum-product algorithm (SPA) for LDPC codes, which is suitable for serial concatenated codes, is proposed in this paper. The proposed algorithm minimizes the number of errors by using the failed check nodes (FCNs) in LDPC decoding. Hence, the error-correcting capability of the serial concatenated code can be improved. The number of FCNs is simply obtained by the syndrome test, which is performed during the SPA. Hence, the decoding procedure of the proposed algorithm is similar to that of the conventional algorithm. The error performance of the proposed algorithm is analyzed and compared with that of the conventional algorithm. As a result, a gain of 1.4 dB can be obtained by the proposed algorithm at a bit error rate of $10^{-8}$. In addition, the error performance of the proposed algorithm with just 30 iterations is shown to be superior to that of the conventional algorithm with 100 iterations.

• Journal of Communications and Networks
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• v.12 no.1
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• pp.1-4
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• 2010

As a countermeasure to simple power attack, the unified point addition codes for the elliptic curve cryptosystem were introduced. However, some authors proposed a different kind of power attacks to the codes. This power attack uses the observation that some internal operations in the codes behave differently for addition and doubling. In this paper, we propose a new countermeasure against such an attack. The basic idea of the new countermeasure is that, if one of the input points of the codes is transformed to an equivalent point over the underlying finite field, then the code will behave in the same manner for addition and doubling. The new countermeasure is highly efficient in that it only requires 27(n-1)/3 extra ordinary integer subtractions (in average) for the whole n-bit scalar multiplication. The timing analysis of the proposed countermeasure is also presented to confirm its SPA resistance.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.34S no.7
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• pp.9-18
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• 1997

In this paper, we implemented the communication module in the Telephone Network Access Subsystem(TNAS) of the Advanced Communications Processing System(ACPS). We defined some kinds of communication tasks and related resources like several queues which are executed in real-time operating system, and implemented the procedures for processing the user information. Through traffic modeling and simulation, the performance of the Service Processing board Assembly(SPA) is evaluated in the aspets of system utilization and buffer size. The ACPS should accommodate various public networks such as public switch telephone network, packet switchen data network, frame realy netork, and ATM network. The communications module proposed in this paper could be used inthe interface beween the SPA and the High Speed Network Adaptor of other network interface subsystems.

• YAKHAK HOEJI
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• v.43 no.1
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• pp.85-90
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• 1999

FTY720, a novel immunosuppressant, elevated the level of endogenous sphingoid bases in a dose-dependent manner within 3 hr in $LLC-PK_1$ cells. The relative molar ratio of sphingoid bases expressed as sphingosine/sphinganine (SPN/SPA), a biomarker of altered sphingolipid biosynthesis, in $10{\;}{\mu}M$ of FTY720 showed tow-fold increase as compared with the one in control culture. FTY720 under the serum-free medium condition increased only cytosolic free sphingosine concentration, not sphinganine concentration in a time-dependent manner over the 8 hr incubation under the same condition as in serum free cultures, the SPN/SPA ratio began to fluctuate and the number of floating cells as an indicator of cytotoxicity was increased 8 hr after the addition of FTY720 to cultured cells. These results suggest that the process of FTY720-induced cell death in $LLC-PK_1$ cells.