• Bulletin of the Korean Chemical Society
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• v.17 no.12
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• pp.1112-1117
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• 1996

The electronic structures of twenty-seven isomers of a macrocyclic fulleropyrrolidine are investigated with semi-empirical extended Huckel (EH) molecular orbital method. The geometry of each isomer is determined by the molecular mechanics and dynamics methods based on UFF (universal force field) empirical force field. The calculated geometries, such as the carbon-carbon distances of the fullerene moiety, are in good agreement with those of related fullerene derivatives. The EH calculation shows that the formation of macrocyclic pyrrolidine ring on fullerene moiety results in the reduction of the HOMO-LUMO energy gap. From the graphical analysis of the DOS (density of states), PDOS (projected DOS), and MOOP (molecular orbital overlap population) curves, we can find that this reduction is due to splitting of the HOMO of fullerene moiety, which results from the symmetry-breaking and the distortion of the buckminsterfullerene framework from its ideal icosahedral structure.

• Bulletin of the Korean Chemical Society
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• v.19 no.2
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• pp.207-211
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• 1998

Potentiometric characteristics of DOS plasticized PVC-based membranes containing upper-rim calix[4]crown neutral carrier to various metal cations and protonated alkylamines have been examined. Although the calix[4]crown-based membrane electrodes exhibited substantial emf responses to alkali and alkaline earth metal cations, their high detection limits (- log[Cs+]=4.5) and sub-Nernstian response slopes (48 mV/pCs+) to the most selective cation, cesium, indicate that the metal cation complexing ability of calix[4]crown is much weaker than that of macrocyclic crown ethers. However, the calix[4]crown-based membrane electrodes exhibited near-Nernstian response slopes (56 mV/decade for hexylNH3+) with low detection limits (log[hexylNH3+]= - 6.7) to most alkylammonium ions compared to those of blank (DOS plasticized PVC membrane with no ionophore) or crown ether-based membranes. While the selectivity patterns of blank and crown ether-based membranes are determined primarily by the lipophilicity of alkylammonium ions, the membranes doped with calix[4]crown ionophore could effectively discriminate the steric shapes of nonpolar alkyl groups of alkylammonium ions.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.7 no.3
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• pp.3-10
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• 1997

Computer viruses are increasing in number and are continually intellectualized as well. To cope with this problem, anti-virus tools such as a scanner and the monitoring program have been developed. But it is not guaranteed that these softwares will work in safety under MS-DOS' control. If the virus is run first, it can avoid the monitoring of anti-virus software or even can attack the anti-virus software. Therefore, anti-virus programs should be run before the system is infected. This paper presents a new PC starting mechanism which allows the PC system to start from a clean state after booting. For this mechanism, we build a new disk file system different from DOS' file system, and manage the two file systems heterogeneously. Our system is strong against boot viruses and recovers from infections automatically.

• Iberoamérica
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• v.13 no.1
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• pp.1-39
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• 2011

O presente estudo tem como objetivo principal analisar a influência de vocabulários de origem africana em uso no português brasileiro(PB). A fim disso, observamos os tipos e as características das línguas africanas. E ainda, para compreender a situação atual de uso desses termos no Brasil, apresentamos um panorama do registro dos vocábulos de origem africana no PB, e organizamos os vocabulários em três categorias, especialmente, nos registros dos séculos XIX e XX. Em primeiro, a categoria 1 pode ser usada em qualquer interação social, contrastando com as outras duas categorias. Em segundo, a categoria 2 é constuída de termos informais, de uso coloquial que, eventualmente, dependendo da situação, são substituídos por outras. Por último, a categoria 3 é de termos marcadamente informais, de uso restrito. Através disso, comparamos os registros anteriores com os dados obtidos da nossa pesquisa. Com os resultados, podemos reconhecer a estabilidade e o dinamismo do uso desses termos hoje no PB.

• Iberoamérica
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• v.13 no.1
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• pp.211-254
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• 2011

O presente trabalho pretende explorar a relação entre a língua nacional e a construção da idenidade nacional no Brasil, materializando os enunciados da "Casa-grande & Senzala" de Gilberto Freyre e os discursos cruzados entre Freyre e romancistas. Atualmente, o português brasileiro é uma manifestação mais extensa e mais profunda da alma multiforme da nacionalidade brasileira como a língua é um tópico essencial no processo de constituição da nacionalidade, ao lado da geografia, da história e da étnia. Junto com o português brasileiro, como o idioma oficial do Brasil, tradições, ideias nacionais se difundiam por todos os habitantes dessa comunidade imaginária. Ao invés dos temas clássicos(como a mestiçagem e a história da vida privada) de Gilberto Freyre, neste trabalho, discutimos as interpretações que Gilberto Freyre fez pelo prisma do luso-tropicalismo sobre a língua e a identidade nacional no Brasil, considerando o cruzamento da Casa-grande e da Senzala representadas na estrutura das obras dos romancistas brasileiros.

• Computational Structural Engineering
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• v.3 no.4
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• pp.37-39
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• 1990

BUILDS 프로그램은 건물구조의 해석에서부터 도면화까지의 일관작업을 MS-DOS 등의 제한된 메모리상에서도 가능하도록 한 건물설계의 일관시스템(Integrated BUIL ding Design System)으로서, 각 작업에 따라 여러개의 부시스템(subsystem)으로 프로그램을 구성하고 이들을 집대성한 것이다.

• Bulletin of the Korean Space Science Society
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• 2006.10a
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• pp.31-31
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• 2006

• Journal of Preventive Medicine and Public Health
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• v.23 no.1 s.29
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• pp.106-116
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• 1990

This study was conducted to investigate of water qualities in the upper and middle reaches of the Han River. For this purpose, water was sampled at Kwangjin and 1st Han-River Bridges of the Han River in Seoul and analysed from August, 1988 to September, 1989. The results are summarized as follows : 1. Water quality at 1st Han-River Bridge was more polluted than that at Kwangjin Bridge. 2. Except biological oxygen demand (BOD), turbidity, suspended solid (SS), dissolved oxygen (DO), DO saturation (DOS), ammonia nitrogen ($NH_3-N$), nitrite nitrogen ($NO_2-N$) and chloride ion ($Cl^-$) at Kwangjin and 1st Han-River Bridges were lower as compared with the previous data before redevelopment of the Han River. 3. SS, DO and pH at Kwangjin and 1st Han-River Bridges could be classified to the 1st grade in environmental water quality standard. DOS at Kwangjin Bridge was over 100% and that at 1st Han-River Bridge was below 100% in the Han River. BOD at Kwangjin Bridge could be classified to End grade and that at 1st Han-River Bridge to 3rd grade in environmental water quality standard. 4. The higher the level of water was, the lower the levels of turbidity and SS, and $NH_3-N$ was decreased with increasing water level at 1st Han-River Bridge. DO was decreased as water temperature went up but DOS was increased with DO. BOD was positively correlated with nitrite-nitrogens. 5. Turbidity and SS at the both sites and Chloride ion ($Cl^-$) at Kwangjin Bridge were increased in July and August. And DO at the both sites and $NH_3-N$ at 1st Han-River Bridge were decreased in at July and August.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.6 no.3
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• pp.12-23
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• 2007

The purpose of this studγ if to understand problem of present bus scheduling system and to develop optimal bus scheduling model which improve bus passenger's degree of satisfaction(DOS) and bus company's operation efficiency at the same time. This study developed optimal bus scheduling model, which reflected bus passenger's degree of satisfaction(DOS), applied to existing model that summery of bus operation cost($C_o$), passenger queuing time cost($C_{pw}$) and passenger travel time cost($C_{pl}$). And optimal bus scheduling model which developed in this study is optimized that using LINGO program based on linear program. Also by using the general case in Busan, compare total cost of present bus scheduling system and existing scheduling model with total cost of optimal bus scheduling model which reflected bus passenger's degree of satisfaction(DOS).

• Transactions of the Korean Society of Mechanical Engineers A
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• v.23 no.11 s.170
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• pp.2014-2021
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• 1999

The present investigation is concerned with the degradation characteristics of cast stainless steel(CF8M), exposed to the $\sigma$-phase degradation at $700^{\circ}C$. In the present paper, the degradation of CF8 M at $700^{\circ}C$ is evaluated by a non-destructive test, DL-EPR(double loop electrochemical potentiokinetic reactivation). The surface of specimens is observed by using scanning electron microscopy after DL-EPR test. Also. chromium contents of matrix, grain boundary and ferrite phase are analyzed by electron probe X-ray micro analyzer. Through the experiments, the following results are obtained 1) The degree of sensitization(DOS) of CF8M aged up to 15hr at $700^{\circ}C$ is increased with acing time while that is decreased with aging time from 15hr to 150hr. 2) The impact energy decreases with increase of $\sigma$-phase while DOS increases with $\sigma$-phase until aging time reaches to 15hr. After the aging time. 15hr, the $\sigma$-phase and the rate of impact energy with respect to aging time decreases. Therefore the degradation behavior of the CF8M can be evaluated by comparing SEM micrographs and the value of DOS.